(CBS News) A suicide bomb attack on a bus in Russia is raising concerns about security at the upcoming Winter Olympics, which will be held in Sochi in February.
This bombing was not the deadliest of a string of terrorist attacks in Russia. But it had three crucial elements that make it stand out: it killed six people, it was apparently carried out by a female suicide bomber, and it was captured on a video camera.
A dashboard camera of the sort in common use in Russia captured the explosion.
The attack took place in the southern city of Volgograd -- formerly Stalingrad -- close to the Caucasus region of southern Russia, still seething with resentment over Moscow's suppression of the militant separatist movement there.
Alexei Mukhin, a spokesman for the Russian investigating agency, said surviving passengers identified the suicide bomber as a woman -- a so-called black widow -- known to be involved in the militant movement in nearby Dagastan.
She's not the first black widow and, the Russians fear, she won't be the last.
The Russians are calling the bombing a test shot ahead of the upcoming Sochi Winter Olympics this coming winter. Militant groups, they say, want to create an atmosphere of fear and panic. And the Russians may have another reason to worry -- blow-back for their support of the Assad regime in Syria says CBS News security consultant, Juan Zarate. He said, "You have the militant and terrorist groups that have operated for a number of years in the caucuses that present a threat like we saw in this bus bombing. But we also see future threats emerging out of Syria where Russia is playing the role of the lead villain where militants and jihadis from around the world may decide they want to attack Russia."
Sochi is already shaping up as possibly the tightest Olympics security operation ever, CBS News' Mark Phillips reported on "CBS This Morning." Attacks like this one, he said, aren't going to make the atmosphere any lighter.
Watch Phillips' full report above.