An explosion in the St. Petersburg metro on Monday has left at least nine people dead, according to Russian state media.

Russian news outlet RBK reported that police were currently searching for two people in connection with the bombing, following initial reports from Russian news website Fontanka that the police had issued a manhunt for a suspect who entered the Petrogradskaya station 20 minutes before the explosion.

A law enforcement official latertold Russian mediathat they are investigating the possibility of a suicide bomber.

At least 50 people have been reported injured from the blast, state media reported. Russia’s state investigative committee said on Monday that it had opened a criminal case over the explosion on charges of terrorism, adding that it would consider all other possible motives.

President Donald Trump denounced the bombing when asked about it by reporters, saying it was a “terrible thing – happening all over the world – absolutely a terrible thing.” White House press secretary Sean Spicer also condemned the explosion during Monday’s daily press briefing and said Trump and Russian president Vladimir Putin have not yet spoken about the attack.

The St. Petersburg subway press office confirmed an explosive device was set off on a train, according to the Associated Press.

The blast reportedly occurred while a train was moving between two stations - Tekhnologichesky Institut and Sennaya Ploshchad.

Another bomb was found and deactivated at a different St. Petersburg metro station, according to Russian antiterrorism officials. That station, Vosstaniya Square, is about 20 minutes by car from the site of the blast.

Earlier reports had suggested there were two blasts, but the latest information from Russian news agencies indicates there was only one.

Here's a look at the aftermath of the blast:

Russia St. Petersburg Explosion Metro Subway Train

Foto: A subway train hit by an explosion at the Tekhnologichesky Institut subway station in St. Petersburg on Monday. source AP Photo/www.vk.com/spb_today via AP

The St. Petersburg metro closed all stations in response to the deadly blast.

Russian President Vladimir Putin, who was in St. Petersburg when the blast occurred, said in a statement that authorities were considering all possible motives, including terrorism.

Here's a map of the affected stations (Russian state media initially reported at least 10 people had died; that number was revised throughout the day):

St. Petersburg Russia Explosion Metro Map

Foto: source Reuters

Various websites and social-media users have posted pictures of blown-out train doors and injured people on the station platform, which appears to be at a stop in the center of Russia's second-biggest city.

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