we have more on that from elizabeth palmer. liz? >> reporter: good evening, scott. both metropolitan police and the london marathon organizers are watching events in boston very closely and hoping for information from u.s. authorities that would indicate whether or not there is now an increased risk of attack here in london. the race is due to go on sunday, more than 37,000 runners have been signed up and, of course, there will be many more thousands of spectators along that 26 miles course. now, the former head of counterterrorism of the metropolitan police told us earlier this evening that even if there is no hard evidence of an increased risk the risk of copy cat attacks will be -- will be assumed to have gone up. so the police will go back over all the intelligence chatter they've had over the last few days very carefully and probably even resurvey the route for what they would consider vulnerable areas in case they have to beef up security in those areas. but bottom line he said really along such a long course there is there isn't a great deal they can do at th

. >>> the london marathon is going forward, despite the horrific boston marathon attack, as elizabeth palmer reports for wjz. police and race organizer says they are closely reviewing security measures. >> reporter: the london marathon is due to start just after 9:00 this coming sunday. and thousands of spectators will line the course. but before that, there's another huge public event. rehearsals have already begun for former prime minister marg red thatcher's funeral, tomorrow. bill bratton is boston's former police commissioner. >> reporter: i can guarantee, within a few minutes of the event in boston yesterday, brittish police services were on the phone to their colleagues in the united states. and have probably been in constant touch since, trying to identify, is there any potential relationship between the events in boston yesterday and the upcoming events here in britain over the next week? >> reporter: even if there is no hard evidence that london's events are directly threatened, police will take the risk of copycat attacks very seriously. as for the runners, few have been put off.

elizabeth palmer reports crews have started to clear debris from the site of the disaster. >> reporter: until yesterday rescuers were still bringing occasional good news, here a garment worker pulled alive from the ruins five days after the building collapsed. but he's probably among the very last. today the bangladeshi army has brought heavy equipment in to board tunnels to the wreckage. nonetheless, families of the missing surround the site clinging to hope. this girl explains she was rescued after three days but her mother is somewhere under the rubble. on sunday the police brought the building's owner back to the capital. they say he was trying to escape to india. workers and labor activists have been protesting all weekend against unsafe conditions at bangladeshi garment conditions. yesterday when the crowd learned that he was under arrest, they cheered. but that news brought no comfort at all to those who lost loved ones in this latest disaster. for cbs news this morning, elizabeth palmer, london. >>> more than 11 1/2 years since the trade center was brought down, a new milestone

elizabeth palmer is her name, she's in london. rning. well, it was an absolutely enormous egg, the egg of an elephant, and it sold just a short time ago for three times what the auction house, christie's, had expected. it went for 66,000 british pounds, that is over $100,000. at this morning's auction, rich collectors were up against museums and galleries worldwide because elephant birds' eggs are as rare as any. james is the head of science and natural history at christie's auction house in london. >> that's probably why a predator got into it to eat. >> reporter: madagascar, an island off the east coast of africa, was home to the elephant bird, the largest that ever lived. it laid such jumbo eggs that 120 chicken eggs could fit inside just one of them. but the bird was hunted to extinction between 300 and 400 years ago. in the movie "raiders of the lost ark," harrison ford was the dashing guardian of rare antiquities, fighting villains out for personal gain. conservationists say this sort of problem is not just a made-in-hollywoo