Eleven people were killed and dozens more injured in an explosion inside the subway of one of Russia's largest cities.
The explosion happened on a subway car between the St. Petersburg Metro stations of Tekhnologichesky Institut and Sennaya Ploshchad Monday afternoon, RT reports. At least 11 people were killed and another 45 were injured, the BBC says.
The explosion may have involved a device that was filled with shrapnel, The Telegraph says.
Only one explosion has been confirmed, but officials did say they found and deactivated another device at a different St. Petersburg subway station, The Associated Press says.
No group has claimed responsibility for the attack, but President Vladimir Putin called the incident a "possible terrorist attack," The Telegraph says.
The U.S. State Department is asking U.S. citizens in Russia to contact their loved ones directly or check-in on social media to let them know you're safe. Facebook has activated its safety check for anyone in the area to let people know you're OK.