A suicide bomber was behind a blast on the St Petersburg subway that killed 14 people, Russian investigators say, while authorities in the Central Asian nation of Kyrgyzstan identified a suspect as a Kyrgyz-born Russian citizen.
There was no immediate claim of responsibility for the Monday afternoon attack, which came while President Vladimir Putin was visiting the city, Russia's second biggest and Putin's hometown.
Russia's health minister has raised the death toll from 11 to 14 and said 49 people are still hospitalised. City Hall authorities said there were several foreign nationals among those killed and injured but would not offer detail. The foreign ministry of the Central Asian nation of Kazakhstan said one of its citizens has been killed in the attack.
Residents have been bringing flowers to the stations near where the blast occurred. Every corner and window-sill at the ornate, Soviet-built Sennaya Square station was covered with red and white carnations.
Russia's top investigative body said in a statement that investigators have identified a man whose body parts were found on the train and who is suspected to be a suicide bomber.
Kyrgyzstan's State Committee for National Security identified one suspect as Kyrgyz-born Russian national Akbarzhon Dzhalilov, aged between 21 and 22. It was not immediately clear if the two statements related to the same person.
The Interfax news agency said authorities believe the suspect was linked to radical Islamic groups and carried the explosive device onto the train in a backpack.
The entire subway system in St Petersburg, a city of 5 million, was shut down and evacuated before partial service resumed six hours later.
Monday's explosion occurred as the train traveled between stations on one of the city's north-south lines. The driver appeared in front of reporters on Tuesday looking tired but not visibly shaken by the events of the previous day.
Alexander Kavernin, 50, who has worked on the subway for 14 years, said he heard the sound of a blast while his train was running, called security and carried on to the next station as the emergency instructions prescribe.
"I had no time to think about fear at that moment," he said.
Four stations on the subway were closed again Tuesday due to a bomb threat, but later reopened.
