A 25-year-old has been arrested over a high-speed motorway crash in which two people were killed and another six injured.
The man, from east London, was held by Hertfordshire Police on suspicion of causing death by dangerous driving after the smash, which happened in the early hours of this morning.
Two BMWs collided on the M1 near Watford in Hertfordshire shortly before 2.40am, killing the driver and rear seat passenger of one of the cars.
Witness Basit Nasir told the Evening Standard that the BMWs "appeared to be having a high-speed race" and had sped past him at around 140mph.
He said: "It was total mayhem. There was mangled metal everywhere. It was foolish of them to drive at this sort of speed. It was raining as well."
Mr Nasir said that four men in a Mercedes arrived at the crash scene and scuffled with survivors.
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The 24-year-old was unarmed and the incident is not being treated as terror-related.
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