Putin vows investigators will soon identify cause of St. Petersburg metro blast

Russian President Vladimir Putin expects that investigators will soon get to the bottom of what caused Monday’s blast in St. Petersburg’s metro.

The president said that now the investigators are looking into various theories, including those linked to terrorism. "The causes (of blast) are unclear, that’s why it is still early to speak about this now. The investigation will determine what happened," Putin said at the meeting with Belarusian President Alexander Lukashenko.

Putin visits scene of St. Petersburg metro blast, lays flowers in memory of those killed