Lithuanian President Dalia Grybauskaite and Viktoras Pranckietis, the speaker of the Seimas, have extended their condolences to the people of Russia over Monday's explosion on a subway train in St. Petersburg that killed at least 10 people and injured around 50 others.

The president "underlined that Lithuania condemned this brutal act of violence directed at innocent people" and "wished strength and fortitude to the victims' families and loved ones", her press office said.

Lithuanian Prime Minister Saulius Skvernelis said in a press release that violence could never be justified.

Estonian Foreign Minister Sven Mikser on Monday sent his condolences to Russian Foreign Minister Sergey Lavrov in connection with the losses of life caused by an explosion in the St. Petersburg subway.

"My sincere condolences to the families and friends of the victims and I wish a speedy recovery to those who were injured," Mikser said. "Our thoughts are with the loved ones of the victims and the injured and with everyone affected by this tragedy."

On Monday evening people laid flowers by the Russian embassy in Riga to commemorate victims of the subway blast in St.Petersburg.

People had brought flowers and lit candles by the embassy.

An explosion Monday afternoon ripped through a subway train in St. Petersburg, killing at least 10 people and injuring 50 others, the spokesman for the city's governor told Russian television. The unidentified explosive device went off at 2:20 p.m. on a train that was leaving the Technology Institute station and heading to the Sennaya Square station.

There was no immediate claim of responsibility for the blast.

The blast came as Russian President Vladimir Putin was visiting the city, his hometown.