Petro Pochynok, 34, of north London, is charged with conspiracy to commit arson with intent to endanger life.
He was arrested in Chelsea, west London, on Monday and appeared at Westminster Magistrates Court on Wednesday morning, where he appeared in a grey tracksuit and spoke only to confirm his name and details. He was remanded in custody to appear at the Old Bailey on 6 June.
He is the second Ukrainian national to be linked to the incidents after Roman Lavrynovych, 21, of Romford, was charged with three counts of arson with intent to endanger life.
A Romanian national, Stanislav Carpiuc, 26, of Romford, has also been charged with conspiracy to commit arson with intent to endanger life.
They appeared before magistrates on 16 and 20 May respectively, and were remanded to re-appear at the Old Bailey with Pochynok.
The 34 year old is accused of conspiring with the other two defendants “and others unknown” to damage a property using fire, intending to do so, as well as intending to or being reckless with regards to whether lives were endangered, according to police.
The charges are related to three fires – between 8 and 12 May in north London.
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The latest took place in the early hours of 12 May at a house in Kentish Town where the prime minister lived with his family before the election. Damage was caused to the property’s entrance, but nobody was hurt.
Another blaze, involving a car on the same street, happened on 8 May.
A fire also broke out at the front door of a house linked to Sir Keir in Islington on 11 May. One person was taken to safety via an internal staircase by crews wearing breathing apparatus.
The investigation into the fires is being led by the Met’s Counter Terrorism Command, as they relate to such a high-profile public figure.
