A car exploded into flames on Thursday just metres from Prime Minister Keir Starmer's £2million north London home.
A 21-year-old man was arrested and detained in the early hours of Tuesday on suspicion of arson with intent to endanger life.
Counter-terrorism police are now investigating three suspicious fires, including the vehicle blaze on May 8 and two separate incidents at properties linked to the PM.
The car, a Toyota RAV4, was completely destroyed in the explosion.
A car exploded into flames just metres from Prime Minister Keir Starmer's £2million North London home
The Daily Mail
Shocking footage shows the moment the dark blue Toyota RAV4 burst into flames on VE Day last Thursday.
The night sky turned orange as thick smoke poured into the air.
In the early hours of Monday morning, a fire erupted in the doorway of a home owned by the Prime Minister.
The blaze at Starmer's townhouse followed another suspicious fire at a property in north London on Sunday.
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The night sky turned orange as thick smoke poured into the air
The Daily Mail
The Metropolitan Police confirmed the arrest relates to all three incidents, which are being treated as suspicious.
A spokesperson said: "The investigation team are also considering two other incidents - a vehicle fire in NW5 on 8 May and a fire at the entrance of a property in N7 on 11 May."
Scotland Yard's SO15 counter terrorism command is leading the investigation as a precaution due to Starmer's status.
Forensics officers were seen combing for evidence outside the property after the latest blaze.
The car was completely destroyed in the explosion
The Daily Mail
The Prime Minister thanked the emergency services for their work.
His spokesperson said they were unable to comment further due to the ongoing investigation.
The Prime Minister's official residence is in Downing Street.
