A suspect in the killing of pro-war Russian blogger Vladlen Tatarsky has been charged with terrorism, Russian officials say.

Darya Trepova was taken to a Moscow court on Tuesday after her arrest the previous day in St Petersburg.

The court ruled the 26-year-old should remain in custody until 2 June.

This comes as a little-known group, the National Republican Army, which has vowed to fight the Putin regime, claimed it carried out the attack.

Tatarsky, 40, was killed on Sunday in a blast in a cafe in St Petersburg where he was due to give a talk. More than 30 people were injured.

In a video released by the authorities on Monday - most likely recorded under duress - Ms Trepova was heard admitting she brought a statuette to the cafe that later blew up. 

But she did not say she knew there would be an explosion, nor did she admit any further role.

Russia's Investigative Committee, which looks into major crime, said she had been charged under the criminal code with "a terrorist act carried out by an organised group causing intentional death" and the "illegal possession of explosive devices by an organised group".

The committee added that it had evidence the attack was organised by Ukrainian security services with the help of jailed Russian opposition leader Alexei Navalny's Anti-Corruption Foundation.

The foundation, which has released a series of exposés of corruption involving President Vladimir Putin's entourage, said it was "very convenient" for the Kremlin to blame its critics when Navalny was due to go on trial soon for extremism.

In a separate development on Tuesday, the National Republican Army said it organised the bombing "without any help from foreign structures, let alone security services". Its statement was carried on the Rospartizan (Russian Partisan) Telegram channel, 

It added that the bombing was not aimed at peaceful citizens. Darya Trepova was "innocent" and a "hostage of the system", it said.

The National Republican Army provided no evidence to back its claim. 

The group was one of three Russian organisations that signed a declaration in Ukraine last August pledging to fight the government in Moscow.

Exiled former Russian MP Ilya Ponomarev, who tweeted about the group's statement, has previously claimed it was behind the murder of TV commentator Darya Dugina. The daughter of prominent ultra-nationalist Alexander Dugin was blown up by a car bomb last year.

Until then the National Republican Army had never been mentioned publicly before.

Tatarsky (real name Maxim Fomin) had been attending a meeting with supporters in the cafe as a guest speaker late on Sunday afternoon.

A video circulating on social media showed a young woman in a brown coat apparently entering the cafe with a cardboard box.

Images showed the box being placed on a table in the cafe before the woman sat down. Another video showed a statue being handed to Tatarsky.

Tatarsky was a well-known blogger with more than half a million followers, and had a criminal past.

Born in the Donetsk region of eastern Ukraine, he said he joined Russian-backed separatists when they released him from jail, where he was serving time for armed robbery.

He was part of a pro-Kremlin military blogger community that has taken on a relatively high-profile role since Russia's full-scale invasion of Ukraine began in February 2022.

Tatarsky is among those who have gone so far as to criticise the Russian authorities, slamming the military and even President Vladimir Putin for setbacks on the battlefield.

But on Monday, he was awarded the posthumous Order of Courage by Mr Putin.