11 dead after subway bomb blast in St Petersburg
A bomb blast has torn through a subway train deep under Russia's second-largest city, St Petersburg, killing 11 people and wounding about 40 others.
Hours later, anguish and fear rose again when police found and defused a shrapnel-packed explosive device at another St Petersburg station.
There was no immediate claim of responsibility for the attack, which came while President Vladimir Putin was visiting the city, his hometown.
In the past two decades, Russian trains and planes have been frequent targets of terrorism, usually blamed on Islamic militants.
News reports said police were searching for two suspects, and Russian state television showed a photo of one suspect wearing what appeared to be a skullcap characteristic of Russia's Muslim regions.
The Investigative Committee, the country's top criminal investigation body, said it had begun a probe based on the assumption that it was terrorism but added that other possibilities were being considered.
St Petersburg, a major tourist destination famed for its imperial palaces and lavish art museums, had been spared previous attacks.
"From now on, I will be scared to take the subway," said Marina Ilyina, 30, who brought flowers to the station where the train stopped after the bombing. "We in St. Petersburg thought we wouldn't be touched by that."
The explosion occurred in mid-afternoon as the train travelled between stations one of the city's north-south lines.
The driver chose to continue on to the next stop, Technological Institute, a decision praised by the Investigative Committee as aiding evacuation efforts and reducing the danger to passengers who would have had to walk along the electrified tracks.
The National Anti-Terrorism Committee said the death toll was 11, with another 45 people being treated for wounds in hospitals.
Amateur video broadcast by Russian TV showed people lying on the platform of the Technological Institute station, and others bleeding and weeping just after the damaged train pulled in.
"Everything was covered in smoke. There were a lot of firefighters," Maria Smirnova, a student on a train behind the stricken one, told independent TV station Dozhd.
Within two hours of the blast, authorities had found and deactivated another bomb at another busy station, Vosstaniya Square, the anti-terror agency said.
That station is a major transfer point for passengers on two lines and serves the railway station to Moscow.
Russian law enforcement agencies confirmed the device was loaded with shrapnel, and the Interfax news agency said it contained up to one kilogramme of explosives.
The entire St Petersburg subway system was shut down and evacuated, but partial service resumed after about six hours.
Security was immediately tightened at all of the country's key transportation sites, Russia's National Anti-Terrorist Committee said. Moscow officials said that included the subway in the Russian capital.
Mr Putin, who meeting with the president of Belarus at the Constantine Palace on the city's outskirts, offered condolences on national television.
"Law enforcement agencies and intelligence services are doing their best to establish the cause and give a full picture of what happened," a somber-looking president said.
The bombing drew widespread condemnation.
President Donald Trump said it was "absolutely a terrible thing". White House Press Secretary Sean Spicer said the US was prepared to offer assistance to Russia.
Lebanon's militant Hezbollah group, which is backing Syrian President Bashar Assad's forces along with Russia, says the incident was the type of "terrorism" Russia was fighting in Syria.
Most of the terrorist attacks in Russia have been connected to the insurgency in Chechnya and other Caucasus republics in the southern part of the country.
The last confirmed attack was in October 2015 when Islamic State militants downed a Russian airliner heading from an Egyptian resort to St Petersburg, killing all 224 people on board.
The Interfax news agency said Russian police suspect that the explosion on the St Petersburg subway train was caused by a suicide bomber.
The agency quoted an unidentified law enforcement official saying that authorities had identified the suspected attacker as a 23-year old national of an ex-Soviet Central Asian nation. It did not name the suspect or the country.
Russian news reports had previously said that police were seeking a man caught on security cameras who was suspected of leaving a bomb behind him on a subway train.
Russian media published photos of the suspect wearing what appeared to be a skullcap characteristic of Russia's Muslim regions.
Interfax later quoted a law enforcement official saying that the man in the video had gone to police to profess his innocence.