Update, December 30, 8:15am: A second deadly bombing has hit the southern Russian city of Volgograd. The blast which hit a trolley bus during the Monday morning rush hour killed at least 14 people, according to CNN.
Original story, December 29, 11:00am: At least 13 people were killed today as a bomb went off in a train station in the southern Russian city of Volgograd. Russian authorities quickly reported the blast was caused by a female suicide bomber who detonated her explosive device as she was preparing to go through a metal detector.
Russian television network CCTV aired video from the blast, which occurred at 12:45pm local time.
RIA Novosti, a government funded news outlet, reports that officials are treating bombing as an act of terrorism. Though no group has yet to claim responsibility for the incident, the Associated Press points to other recent attacks in the region:
Female suicide bombers, many of whom were widows or sisters of rebels, have mounted numerous attacks in Russia. They often have been referred to as "black widows.
In October, a female suicide bomber blew herself up on a city bus in Volgograd, killing six people and injuring about 30. Officials said that attacker came from the province of Dagestan, which has become the center of an Islamist insurgency that has spread across the region after two separatist wars in Chechnya. She took a Moscow-bound bus from Dagestan, but left it in Volgograd for an unclear reason and took a local bus, where she detonated her explosives.
Russian President Vladimir Putin has ordered law enforcement agencies to beef up security measures, especially in light of the Winter Olympics, which take place in Sochi (over 400 miles to the southwest) in six weeks.
*This post has been updated with a corrected video link.