Investigators have identified the 17-year-old widow of a North Caucasus militant as one of the Moscow suicide bombers, local media reported Friday, citing a Dagestani law enforcement source.

The woman, who detonated explosives at the Lubyanka metro station, was identified as Dzhennet Abdurakhmanova, the widow of Dagestani militant leader Umalat Magomedov who was killed by federal forces in 2009, the Kommersant daily reported.

The newspaper also published a photo of the couple posing casually with pistols.

"She was identified based on information received through a number of channels. There is almost 100 percent certainty that she staged the terrorist attack," a source close to the investigation told the Interfax news agency.

Two female suicide bombers on Monday killed 39 people in attacks on the Moscow subway system. Authorities have linked the attacks to militants from the North Caucasus.

The second suicide bomber who detonated herself at Moscow's downtown Cultural Park metro station has been identified as a resident of the restive North Caucasus republic of Dagestan, an anonymous security service source told media on Thursday.

Russia's North Caucasus republics, particularly Chechnya, Dagestan and Ingushetia, have been plagued by violence, particularly against law enforcement officers, which local rebels see as representing the Russian authorities.