MOSCOW — A suspect in the deadly subway bombing in St. Petersburg, Russia, was reportedly identified by authorities Tuesday as a Kyrgyz-born man in his early 20s.

The central Asian state of Kyrgyzstan's State Committee for National Security said it believed Akbarzhon Jalilov, born in Osh in 1995, was linked to the attack but his exact role was unclear, the Associated Press and Reuters reported.

The explosion, which came while President Vladimir Putin was visiting the city, his hometown, tore through a train under Russia's second-largest city, killing 14 and wounding close to 50. Police later found and defused a shrapnel-packed explosive device at another station.

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Interfax news service cited an unidentified Russian law enforcement official saying that investigators believe a single suspect left the second device before blowing himself up on the train, according to the Associated Press. None of the reports could be independently confirmed by NBC News.

Russia is home to a large diaspora of Central Asian migrants who flee poverty and unemployment in their home countries for jobs in Russia.

In the past two decades, Russian trains and planes have been frequent targets of terrorism, usually blamed Chechen separatists or Islamic militants, but 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."

Putin laid flowers at St. Petersburg's Tekhnologichesky Institut station late Monday, according to official state news service TASS. The president stepped out of his car in Moskovsky Prospekt Avenue with a bunch of scarlet roses.

The blast happened when the train was between the Sennaya Ploschad and Tekhnologichesky Institute subway stations. There was praise for the driver, who took the damaged cars forward so that victims could be treated more quickly by first responders.

The second device was found at Ploshchad Vosstaniya station. It was loaded with shrapnel and contained up to 2.2 pounds of explosives, Interfax reported.

The subway was closed for several hours while authorities checked the system for other threats. It was reopened later with tighter security and the city offered free bus travel.

In a phone call with Putin, President Donald Trump offered condolences, the White House said in a statement Monday night.

Trump also pledged to support Russia's response to the attack and its pursuit of justice, the statement said.

"Both President Trump and President Putin agreed that terrorism must be decisively and quickly defeated," the statement said.

ISIS claimed it had created a bomb brought down a Russian MetroJet passenger jet over the Sinai desert in Egypt in 2015. The Dec. 25, 2016, crash of a Russian plane near Sochi that killed 92 people, including members of the Red Army Choir, is widely believed to have been due to a bomb, but no official cause has been given.

Previous attacks in Russia include the bombing of a Moscow-to-St. Petersburg train on Nov. 27, 2009 that left 26 dead and 100 injured.

On Jan. 24, 2011, a suicide bomber blew himself up at Moscow's Domodedovo Airport, killing 37 people and wounding 180. The same airport in August 2004 saw Islamic suicide bombers board two airplanes and bring them down, killing a total of 90 people.

—Alastair Jamieson reported from London.