A fourth man has been arrested over a series of fires at properties and a car linked to Prime Minister Sir Keir Starmer.
The 48-year-old man was detained at London Stansted Airport on Monday and is being questioned on suspicion of conspiracy to commit arson with intent to endanger life, the Metropolitan Police said.
Three other men have been charged over the fires: Ukrainians Petro Pochynok, 34, and Roman Lavrynovych, 21, and Ukrainian-born Romanian national Stanislav Carpiuc, 26.
Lavrynovych is charged with three counts of arson with intent to endanger life, while Pochynok and Carpiuc are accused of conspiring to commit arson with intent to endanger life. They are due to appear at the Old Bailey on Friday.
Forensics officers outside the house in Kentish Town, where there was a fire on 12 May. Pic: PA
It comes after a fire in the early hours of 12 May at a house in Kentish Town, north London, where Sir Keir lived with his family before the election.
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May 13: Man arrested over a series of arson attacks after the prime ministerβs house and car were set on fire
Damage was caused to the property’s entrance, but nobody was hurt.
A car was also set alight in the same street on 8 May.
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Another fire took place on 11 May at the front door of a house linked to Sir Keir that was converted into flats in Islington. One person was taken to safety by crews wearing breathing apparatus.