TODAY | January 21, 2014
>>> let's turn to security concerns in russia . with the start of the winter olympics 16 days away. in the wake of a video vowing an attack, authorities are searching for so-called black widows who could be used to carry out the threat. richard engel in moscow once again. richard, good morning to you.
>> reporter: good morning, matt. russia says everything is under control. but at the same time, says it's searching for missing suicide bombers , particularly women.
>> reporter: wanted posters are being distributed to russian police stations for three more black widows , suspected suicide bombers on the loose. young muslim women , they join rosana who may have slipped into the olympic host city of sochi. 22 years old, rosana was made a black widow last year when russian forces killed her husband, also a suspected militant. that scar on her cheek reportedly came from russian troops. the four women are from the caucuses, the heart of russia 's islamic insurgency. but why use women? why black widows ? it's the signature tactic of militants from north caucuses where russia is in the midst of a tit for tat war. and don't underestimate the black widows , they were used to take 800 hostages in 2002 . nearly 200 were killed when russian commandos ultimately stormed in. now, despite having placed 40,000 troops to guard the ring of steel around the olympic venue, russia is desperate to find the missing widows.
>> the problem is, you need to think about government intelligence , preventive measures, that's not about number of troops you can put on the ground.
>> reporter: police warn terrorists may be targeting the olympic torch relay , which means these games may be attacked even before they begin.
>> reporter: the intelligence is actually quite specific with police worried the relay could be attacked over the next three days. matt?
>> richard engel in moscow for us, thank you very much.