A blast that ripped through a train as it traveled between two central subway stations in Russia’s second-largest city on Monday killed at least 11 people, injured at least 30 and panicked the heart of one of the world’s most renowned urban centers.

It also cut across the fault lines of a country grappling with its first signs of political upheaval in years. Some are calling for increased security measures; others warned of an impending crackdown.

Authorities launched a terrorism investigation that centered on a single bomber who left an explosive device at one central station before boarding a train and detonating a second device. But officials gave no immediate confirmation of details on the identity of the bomber or any suspected affiliation in the blast, and no one claimed responsibility.

About 11 p.m., Russian President Vladimir Putin made a public, if carefully guarded, appearance and placed a bouquet of roses at the subway station where the train came to a halt after the blast. Above ground, children placed roses and tea-light candles at a makeshift memorial outside Sennaya Ploshchad station, the busy central interchange from which the train departed before the bomb went off.

Some of Putin’s opponents expressed concern that the Kremlin might use the attack as an excuse to curtail a nascent movement that brought tens of thousands of people into the streets eight days earlier to protest official corruption.





“The actions of the authorities as far as any mass protests are predetermined,” tweeted opposition activist and former legislator Dmitry Gudkov, earning a rebuke from Russian state television, which called his remark a calculated and cynical ploy.

But the blast ignited anger among ordinary residents, too.

“Shock, I felt shock. It’s disgusting,” said Andrei Gontarevsky, 51, who said he manages a small team of construction workers. “It’s unthinkable. This was always a quiet city, and I think it shows the times are turning bad now.”

Alexander Borkov, 31, said the doctors at his local clinic stood for a moment of silence when they heard about the blast. Many called loved ones — he called his wife, Vera. When evening came, he wandered over to the square, alone, visibly shaken and angry.

“This happened because we are fighting a war,” he said quietly, pulling a gray knit cap more tightly over his head. “I walk through those [subway metal detectors] every day, but I know it’s all for show.” Subway personnel often wave through passengers with concealed metal objects like cameras.

“The police grab kids off the square for protesting,” said Borkov, “but they’re not doing what they really need to be: protecting us.”

[The recent history of terrorist attacks in Russia]

1 of 18 Full Screen Autoplay Close Skip Ad × The scene in St. Petersburg after a subway blast killed at least 11 people View Photos An explosion tore apart a train as it traveled between two central St. Petersburg metro stations. Caption An explosion tore apart a train as it traveled between two central St. Petersburg metro stations. April 3, 2017 Men carry an injured person on a stretcher outside a metro station. Alexander Tarasenkov/AFP/Getty Images Buy Photo Wait 1 second to continue.

Security forces fanned out on extra patrols as police helicopters crisscrossed overhead in one of the city’s most celebrated, and tourist-visited, neighborhoods. The area around the Sennaya Ploshchad station is near some of the most famous sights of St. Petersburg, and was the setting of Fyodor Dostoevsky’s novel “Crime and Punishment.”

Shortly after the blast, the entire St. Petersburg subway system was shut down for a time as a precaution, and security was heightened around the city, Putin’s home town, where the Russian leader was holding talks with Belarusan leader Alexander Lukashenko.

Authorities said the blast was caused by an improvised explosive devise that went off in one of the cars as the train traveled from Sennaya Ploshchad about 2:40 p.m.

The operator was able to get the train to the next station, where authorities reached the victims. Pictures broadcast on Russian television showed that the doors had been blown out of the side of one car. Russia’s Federal Security Service said the second device was found and defused at the Ploshchad Vosstaniya station, another central interchange.

[A right-wing militia trains for Russia’s next war]

Russia’s health minister, Veronika Skvortsova, said seven people died at the scene, one died en route to the hospital and two more while undergoing treatment. She said six people remained in serious condition, raising the possibility that the death toll could rise. Authorities said late Monday that an 11th person had died.

Late Monday, a spokesman said Putin was being briefed by law enforcement. Earlier, Putin expressed condolences to the victims’ families in televised remarks, adding: “Naturally, we always probe all theories, both domestic and criminal ones, primarily actions of a terrorist nature.”

Viktor Ozerov, a member of the defense and security committee of the upper house of the Russian parliament, told the Interfax news agency that the attack had “all the characteristics of a terrorist attack.” Other legislators called for increased security measures.

Islamist militants from the North Caucasus have been blamed in more than a dozen major terrorist attacks in Russia since the country fought two civil wars in Chechnya. Russia still faces a simmering insurgency in the neighboring Dagestan province, and in March, six Russian soldiers and six militants were killed in a shootout in Chechnya. But the ­post-Soviet republics of Central Asia have also been a source of Islamist fighters. Interfax, citing sources, said the bomber was believed to be a Kazakh national.

The city of St. Petersburg announced three days of mourning beginning Tuesday. The U.S. Embassy in Moscow joined other countries in expressing condolences.

In Washington, President Trump called the incident a “terrible thing.” He called Putin to express his condolences, according to Putin’s spokesman.

In Moscow, dozens of young people gathered outside the Kremlin to lay flowers at a World War II memorial to the city of Leningrad — as St. Petersburg was called then.

Filipov reported from Moscow. Brian Murphy in Washington contributed to this report.

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