MOSCOW — Explosions at two subway stations in St. Petersburg killed at least 10 people on Monday afternoon, as President Vladimir V. Putin was in the city, Russia’s second largest, for a meeting and a speech, officials said.
Andrei Kibitov, a spokesman for the St. Petersburg governor, told the Rossiya-24 news channel that the explosions had killed about 10 people and wounded at least 50 others.
The subway system was shut after the attacks, which occurred around 2:45 p.m. at the Sennaya Square and Technology Institute stations, in the city center. Both stations are important transit hubs and are normally crowded with passengers, though the explosions occurred before the start of the evening rush.
Mr. Putin, in a televised statement less than an hour after the explosions, said he had spoken with the heads of the special services, including the F.S.B., as well as with law enforcement officials, who he said “will do everything to find out the causes of what had happened.”
Speaking from the Constantine Palace in the Strelna district of St. Petersburg, about 12 miles west of the blasts, he added: “The government, both on the city and federal levels, will do everything to support families of the victims and injured.”
Images circulated on social media showing a damaged subway car and several people lying on a subway platform, apparently with injuries.
The two stations are adjacent on the No. 2 subway line, which runs north-south through St. Petersburg. Both of the stations are transfer points with other subway lines.
Mr. Putin was in St. Petersburg for a meeting with the president of Belarus, Alexander G. Lukashenko, a traditional ally who has recently feuded with the Kremlin, and to give a speech at the All-Russia People’s Front, a political group started by the president.
Public transportation has been attacked in Russia before.
Two subway stations in central Moscow were attacked by suicide bombers on March 29, 2010, killing dozens and renewing fears of terrorism there. The attack was linked to pro-Chechen separatists active with a pan-Caucasus insurgency.
The subway system in Moscow was also twice struck in 2004 by deadly attacks. In February, a bomb detonated inside a train car as it left the Avtozavodskaya station in southeast Moscow, killing at least 39 people, and in September, a suicide bomber detonated explosives at a station north of Moscow, killing 9.