on alert. one year after the raid that killed osama bin laden, al qaeda gears up for revenge. in hiding. a chinese legal activist who escaped from house arrest is believed to be taking refuge in the u.s. embassy. and white house humor. president obama tries for laughs at the expense of mitt romney at the annual white house correspondents' dinner. >> we also both have degrees from harvard. i have one. he has two. what a snob. this is the "cbs morning news" for monday, april 30, 2012. good morning. thanks for joining us. i'm michelle miller.

it was one year ago this week, u.s. special forces raided osama bin laden secret compound in pakistan and killed the al qaeda leader. al qaeda is weaker but remain a threat to americans and u.s. interests and the raid has become a political issue in this year's presidential campaign. tara mergener is in washington with more. good morning. >> reporter: good morning. that's right. this anniversary is quickly becoming a controversial campaign issue. this as americans are warned to be on guard while officials track down leads. the fbi and homeland security department warns, americans need to be on alert ahead of wednesday's one-year anniversary of osama bin laden's death. >> we don't see any active plots under way but we are maintaining our guard. >> reporter: counterterrorism advisers admit al qaeda likely wants payback for killing of its leader, but u.s. officials say the terror group is no longer capable of carrying out a september 11th-type attack.

>> we have taken off the battlefield founding leader. >> reporter: the anniversary of osama bin laden's death comes in the middle of the presidential campaign. republicans argue democrats are trying to use it for political gain. the obama campaign released this web video questioning whether likely republican nominee mitt romney would have made the decision to raid bin laden's compound in pakistan. >> he took the harder and the more honorable path, and the one that produced, in my opinion, the best result. >> reporter: republicans say the video crosses the line. >> it's something that was a unifying event for all americans. and he's managed to turn it into a divisive, partisan, political attack. >> reporter: president obama's campaign says the ad is fair game. >> and osama bin laden no longer walks on this planet today because of that brave decision and the brave actions by the men and women in our military. quite frankly, mitt romney said it was a foolish thing to do a few years ago.

>> reporter: but both candidates agree, more still needs to be done to prevent any future attacks. now, of greatest concern to u.s. officials is al qaeda's yemeni affiliate and master bomb maker. who has survived repeated u.s. taech attempts to kill him. michelle? >> tara mergener in washington, thank you. here in new york, police are trying to determine what caused a van to flip off a highway overpass, killing all seven people on board. the van crossed three lanes of traffic before flying over a four-foot guardrail and falling more than 50 feet yesterday afternoon. it landed in a wooded area of the bronx zoo that's not open to the public. the van landed upside down and was crushed. >> the injuries were quite horrific. in 30 years i've seen something like this once or twice. everybody was taken aback by it. >> police say the victims were wearing their seat belts. all were members of the same family, including three children. no one on the ground was hurt.

police say speed may have been a factor. the bodies of three crew members killed in a yacht racing crash have been found off the pacific coast. a fourth sailor remains missing. the 37-foot aegean was taking part in a 125-mile race from newport beach, california, to ensenada, mexico. debris from the yacht was first recovered saturday. search crews said it looked like had it been through a blender. race officials say it must have collided with a much larger ship like a freighter or tanker. the united states won't say if it's harboring an escaped chinese activists in its beijing embassy. chen gaungchen a blind activist, escaped from house arrest eight days ago. he was driven away by supporters and eventually made his way to beijing. several of his supporters have been arrested and his whereabouts of his family is not known. chen's escape and presumed u.s.

involvement is sure to complicate this week's high-level talks between the u.s. and china. secretary of state hillary clinton and treasury secretary tim geithner are due in beijing for critical military, strategic and economic talks. whit johnson reports. >> reporter: following reports the chinese dissident has taken refuge in u.s. embassy in beijing, state department spokeswoman victoria nuland remained firm. >> i don't have anything for you on that. >> nothing at all? >> nothing at all. >> reporter: the case is extremely sensitive ahead of the annual meeting between the u.s. and china. secreary of state hillary clinton and treasury secretary tim geithner are expected to begin talks thursday, centering on trade, the economy and nuclear tensions with north korea and iran. chen will be the elephant in the room. and reportedly some u.s. officials have departed early to negotiate his fate. >> we're going to make sure we do this in the appropriate way. >> reporter: john brennan stressed the importance of improving chinese/u.s.

relations. >> i'm not going to address the issue of mr. chen right now. we are working very closely with the individuals involved in this, so i'm going to leave it to others in the u.s. government who have responsibility for it. >> reporter: negotiating chen's release will be difficult for both countries, with the administration hoping to avoid accusations of caving on human rights and the chinese fearing too many concessions may embolden other activists. >> i think that the u.s. is not in a position to require that the chinese treat him well if he leaves the u.s. embassy. the best we can hope for is to negotiate safe passage to the airport and exit from the country. >> reporter: there may be some incentive on both sides for a quiet resolution. if not only a presidential election year here in the u.s., but china's communist party is expecting a leadership transition around the same time. whit johnson, cbs news, the white house. the head of the u.n. observer mission in syria says

it's up to syrians to stop the blood shed that's killed more than 9,000 people there. general robert mood arrived in damascus yesterday. activists say two bombs detonated at syrian security headquarters today, killed more than 20 people. a cease-fire was supposed to go into effect april 12th. coming up next, apple's secret to paying lower taxes. plus president obama cracks up the crowd at this weekend's white house correspondents' dinner. we'll have the highlights. this is the "cbs morning news." i'm a coach. , but when i was diagnosed with prostate cancer... i needed a coach. our doctor was great, but with so many tough decisions i felt lost. unitedhealthcare offered us a specially trained rn who helped us weigh and understand all our options. for me cancer was as scary as a fastball is to some of these kids. but my coach had hit that pitch before. turning data into useful answers. we're 78,000 people looking out for 70 million americans. that's health in numbers.

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presidential election over the next six months, we will certainly hear plenty of serious messages and political rhetoric coming from leaders in washington. but on saturday night the nation's capital turned into celebrity central at the annual white house correspondents dinner. president obama serving as roast master general, so to speak. the stars of hollywood and washington, d.c. came together for what has become one of the most talked about events in the nation's capital every year. and as expected, president obama's remarks were more "saturday night live" than state of the union. he took frequent jabs at his republican critics. >> what's the difference between a hockey mom and a pit bull? a pit bull is delicious. i want to especially thank all the members who took a break from their exhausting schedule of not passing any laws to be here tonight. >> the president took aim at his likely opponent in the general

election, mitt romney, while also poking some fun at himself. >> anyway, it's great to be here this evening in the vast, magnificent hilton ball room, or what mitt romney would call a little fixer-upper. he and i actually have a lot in common. we both think of our wives as our better halves. and polls show to an alarmingly, insulting extent, the american people agree. >> and he even joked about the ongoing secret service scandal. >> in fact, i had a lot more material prepared, but i have to get the secret service home in time for their new curfew. >> they didn't look like they liked that too much. all jokes aside, the president used has time on the podium to pay tribute to journalists marie colvin and anthony shadid, both of who died covering the conflict in syria. prceeds from saturday's event

go for scholarships for young journalists. on the "cbs moneywatch," how apple avoids paying millions in taxes and gas prices sink lower. ashley morrison's here in new york with more. >> good morning, michelle. markets overseas got a boost. hong kong's hang seng gained more than 1.5%. sk south korea's index added a fraction. tokyo's nikkei is closed for a holiday. this week we'll get the april jobs report. investors are hoping to see an improvement over the march unemployment numbers but analysts believe the unemployment rate will remain unchanged. on wall street stocks bounced back last week. the dow regained all of its losses for april, adding 199 points for the week. the nasdaq added 68. gas prices continue their downward trickle. according to aaa the cost of a gallon of regular fell a nickel this week. the nationwide average price is now $3.82. that's about nine cents lower than the same price a year ago. apple's profits may be through the roof but the company's tax bill hasn't changed much.

according to a report in "the new york times," apple uses subsidiaries in low tax nations to keep its taxes lower. methods are legal and may have saved apple as much as $2.4 billion last year. and at the box office, make it two in a row for "think like a man." the comedy was the number one movie in america for the second straight week. it made $18 million, raising its domestic total to nearly $61 million. but the big winner this weekend was the comic book sequel "the avengers." it made more than $178 million overseas. it opens here in the u.s. this friday. i don't know, michelle, i think that "think like a man" might be a funny one for us to see. >> both are on my list. must see. ashley morrison here in new york. thanks for joining us. straight ahead, your monday morning weather. in sports, playoff pressure. the l.a. clippers make an incredible comeback against the memphis grizzlies. living with the pain

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here another look at here's another look at today's forecast in some cities around the country. new york, partly sunny, 65. miami, rain, 82. chicago, thunderstorms, 65. dallas, partly sunny, 83. l.a., partly cloudy and 72. now for a check of your national forecast. showers and thunderstorms will stretch from the great lakes to the ohio valley with damaging wind and large hail in some areas.

a few thunderstorms could pop up across the south with southern florida getting as much as 3 inches of rain. the sun will linger over most of new england and it will be windy from the northwest to northern colorado. in sports, the l.a. clippers stun memphis in game one of the western conference series at one point. the grizzlies were on top by 24, but the clippers took the lead on chris paul's free throws with just 23 seconds left in the game. the clippers muzzled the grizzlies 99-98. an ugly night for the celtics against the hawks after a rumble on the floor in the fourth, boston's rondo was tossed for bumping an official. the hawks roll past boston to take game one. in other first-round action, l.a. lakers knock down the denver nuggets 103-88. and the san antonio spurs waltzed over the utah jazz 106-91. in hockey, the coyotes take a commanding lead over the predators in the western conference semis.

in the second period, phoenix scored three times on 19 shots. and after a face-off in the third, shane doan powers one in. phoenix over nashville 5-3 for a 2-0 series lead. in game one of the eastern conference semifinals, danny briere's slap shot in overtime puts the philadelphia flyers over the new jersey devils 4-3. in baseball, tampa bay beat the rangers at home and the rays do it on the strong left arm of david price. he strikes out six. tampa bay over texas 5-2. when we come back, a wake-up call for young diabetes patients. why treating the disease in children is a lot more difficult. [ female announcer ] style is long lasting when hair is nourished

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here's a look at today's forecast in some cities around the country. washington, d.c., partly sunny, 67. atlanta, mostly sunny, 88. st. louis, rain, 79. denver, partly sunny, 75.

seattle, occasional rain at 57. here's another look at this morning's top stories. wednesday marks the one-year anniversary of the raid that killed osama bin laden. white house officials say there is no sign of a specific al qaeda revenge plot but al qaeda is still trying to attack american interests. and it's presumed a chinese legal activists is hiding out in the u.s. embassy in beijing. activists say china and the u.s. are trying to resolve the issue before secretary of state clinton's visit later this week. a disease that normally attacks adults is now being found in the young. it's type 2 diabetes. a new report says doctors are seeing a dramatic increase, especially in overweight teens. and as tony guida reports, is also harder to treat. >> reporter: type 2 diabetes was never seen in young people as

recently as 15 years ago. now it's occurring with alarming frequency. doctors know a major risk factory is obesity. beyond that they were mostly in the dark about this disease. >> very little is known about the right way to both prevent it and to treat it. >> reporter: a new study in "the new england journal of medicine" finds standard treatment for type 2 diabetes in children is ineffective because the commonly prescribed drug metformin prescribed for adults, has a high failure rate in children. but a combination of two diabetes drugs is far more effective in treating children. >> two drugs right off the bat. that's an important finding. >> no added sugars -- >> reporter: important because type 2 diabetes appears to be more aggressive in young people between the ages of 10 and 17. putting them at great risk for life-threatening illnesses typically associated with seniors. >> we want them to grow up and

have healthy lives and not be having heart attacks and strokes at terribly young ages. >> how has it been working out? >> good. >> that wasn't a good good. >> reporter: when it comes to preventing type 2 diabetes, more exercise and a healthier diet are key, but doctors know young people's habits are tough to change. >> the first surprise we saw was, number one, how incredibly difficult it was to effect lifestyle change in these children. >> reporter: extremely difficult as well to get children to take any medicine, let alone two drugs. spotlighting the oldest truth in medicine, better not to get the disease than to have to treat it. tony guida, cbs news, new york. a cdc study says one-third of workers in the u.s. are sleep deprived getting fewer than six hours of sleep per night. almost half of the people work overnight say they're not getting enough shut-eye. we know a little something about that. coming up after your local news on "cbs morning news," singer/songwriter neil sedaka.

i'm michelle miller and this is the "cbs morning news." [ female announcer ] ready for a taste of what's hot? check out the latest collection of snacks from lean cuisine. creamy spinach artichoke dip, crispy garlic chicken spring rolls. they're this season's must-have accessory. lean cuisine. be culinary chic. people will have doubts about taking aspirin for pain. that's why we developed bayer advanced aspirin with micro particles.

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law enforcement agencies on high alert as we ea approach the first year anniversary of the raid that killed osama bin laden. suv plummets off of a highway in new york city and in to the

bronx zoo killing 7 people inside. the investigation in to what went wrong there. a human set back for the prosecution trial resumes for two brothers accused of beating a taminger in northwest baltimore city. ,,,,,,,,,,,,,,

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