report said that 1,000 to 2,000 centrifuges were removed from natanz for unknown reasons.rgets 1,000 centrifuges. so from that, people are drawn to the conclusion, well, stuxnet got in and succeeded. that's the only evidence that we have. >> kroft: the only information that's not classified? >> Ó murchú: yes. >> kroft: and there are lots of things about stuxnet that are still top secret. who was behind it? >> Ó murchú: what we do know is that this was a very large operation. you're really looking at a government agency from some country who is politically motivated, and who has the insider information from a uranium-enrichment facility that would facilitate building a threat like this. >> kroft: an intelligence agency, probably? >> Ó murchú: probably. >> langner: we know from reverse engineering the attack codes that the attackers have full-- and i mean this literally-- full tactical knowledge of every damn detail of this plant. so you could say, in a way, they know the plant better than the iranian operator. >> kroft: we wanted to know what retired general michael hayden

it's important to note if they tried to do it they would have to do it at natanz or fordo which means they get caught. the first is weapons grade uranium. the second component is they would have to have a weapons design and have done all of the various experimentation and manufacturing to actually construct even a crude device and then they would have to figure out a way to deliver that weapon. you have a year estimate from a decision to be able to generate a testicle device and several years to put one on the missile. >> so you have to have the deliver system. >> the weapons grade uranium, weapons design and actually assemble it and the delivery system. >> there would have to be tests of the delivery system, right, or not? >> it depends if they're going to do an implosion device that is sophisticated enough to be put on the tip of a missile, they're probably going to have to test that. if they do a crude gun type device like the weapons that we deployed in world war ii, they might not have to test that. >> if your testimony you say and i quote i believe, meanwhile in the aftermath of

much more challenging than natanz or any of the other facilities. >> reporter: to get at these facilities, the most direct route for israeli warplanes would be due east across jordan and iraq. to most sites, long said, israel will likely deploy its modified f-16 jets carrying 2,000-pound bunker-buster bombs. to fordow, its f-15 jets carrying 5,000 as well as 2,000- pound bombs. but those bombs would have to hit with unprecedented precision. >> it would require six or seven 5,000 pound bunker busters sort of impacting one after another at the same spot. you would have opened essentially a crack or a tunnel down through 80, 90 meters of rock. the idea would be to have one bomb that finally went all the way through into the space where the centrifuges are and then exploded. >> these are very accurate weapons, but getting seven bombs to sort of line up would require using many more than seven bombs on the same point. so you're talking the israelis would have to drop 75 or more weapons on the same aim point to have any confidence at all that this would work. now the problem with that is >> rep

. >> reporter: those include the uranium enrichment site at natanz and the processing plants at isfahan. but there's a newer, harder-to- attack enrichment facility-- revealed in late 2009-- that's buried under 300 feet of rock at fordow, near the holy city of qom. >> so, this is an incredibly challenging target. much more challenging than natanz or any of the other facilities. >> reporter: to get at these facilities, the most direct route for israeli warplanes would be due east across jordan and iraq. to most sites, long said, iael will likely deploy its modified f-16 jets carrying 2,000-pound bunker-buster bombs. to fordow, its f-15 jets carrying 5,000 as well as 2,000- pound bombs. but those bombs would have to hit with unprecedented precision. >> it would require six or seven 5,000 pound bunker busters sort of impacting one after another at the same spot. you would have opened essentially a crack or a tunnel down through 80, 90 meters of rock. the idea would be to have one bomb that finally went althe way through into the space where the centrifuges are and then exploded. >> these ar

but they would likely have to go after the natanz enrichment facility, the iroc heavy water plant, the iranian conversion facility and likely a number of other places. they would need dozens and dozens of aircraft to be able to fly 1,000 miles to those facilities. they don't have the military capability -- i don't assess -- to set the program back very far. that is, they can get to their targets and drop bombs on their targets but senior u.s. defense officials have consistently said that they think israel, at most, could set the program back one to three years and the lower end of that estimate seems more likely to me. >> okay. one to three years. that brings up my next question. how many years has it taken iran to get to this point in its development of nukes? >> they -- the nuclear program started under the shah, so it's been multiple decades, since the 1970s. >> so it's taken 40 years to get to this point. >> yeah. and our counterproliferation efforts in both in the previous administration and this administration has slowed them down appreciably. they continue to make progress. prog

if the subpoenas are asking for documents related to businessman jeffrey thompson natanz is associateding back to 2003. he reportedly donated hundreds of thousands of dollars to local candidates over the years. if michael brown told us that he got money from townsend but says that the probe will show his campaign did nothing illegal. >> the only time we can figure out how to get to the bottom of things is to give -- anytime we can figure out how to get to the bottom of things and give the public confidence in us is a good thing. >> i'm interested to see the outcome. >> this all comes a few weeks after thompson's home and offices were raided by federal agents. and it comes at the same time that the number of the council members are seeking reelection. brianne carter, abc 7 news. >> thanks so much. government inspectors want to know if the washington monument sank or tilted during the earthquake. surveyors are trying to figure out if other changes occurred. they say the results could affect plans for fixing the monument. >> the president plans to visit largo, maryland, to give a speech

. >> it is now natanz of d.c.'s alcohol regulators.ve 90 days to make a decision. -- now in the hands of d.c. alcohol regulators. >> mike sorrentino is in a drug rehab program over a prescription medication problem that he had due to exhaustion. he is banking fans all of their support. if you love rock-and-roll, we have good news. >> motley crew teaming up for a nationwide tou andr with kiss. jean simmons says that his fans can expect live music with everybody playing their own instruments. he created a stir when he called out singer rihanna. >> no karaoke singers allowed. leave that to rihanna-shmianna and everybody else whose name ends with an "a." this is real stuff. >> no response so far from rihanna. >> where did that come from? >> the downside, apparently. >> much more to come in the next hour. >> the latest in the republican presidential race. why mitt romney is at the center of controversy involving an etch a sketch. >> >> a standoff with a terror suspects in france is now in its second day. >> a man sexually assaulted a local

>> well, the bad news is that words in washington don't stop centrifuges in natanz because during thisspector, reported that iran has tripled the pace of production of 20% grade uranium. they're transferring their facilities underground to be immune. and they're racing towards acquiring a nuclear weapon. the words aren't going to stop them. the current sanction regime will not do the job. >> does this move your former boss, prime minister netanyahu, one step closer to taking military action against iran? >> well, there's still one last chance to overt an attack, and that's if america and the world immediately implement devastating sanctions that will bring iran's regime to the brink of a collapse. that's the one thing that can prevent the need for attack, but we're not there. the current sanctions -- the most important of them are only going to play in in june. we ought not to be waiting for june. we should do it right now. >> hmm. dan senor? >> if the sanctions don't work, if diplomacy doesn't work, the clock could run out to the point where israel doesn't have the military capability