Mobile phone footage has captured the moment a man screamed at a family: 'Get ready to die.'
Terrified family members were confronted by the man, recorded screaming and shouting at them reportedly off the M27 on the way to Portsmouth on Saturday at 11.30am.
The video shows him with his hand holding on to the inside of the family's car, before screaming about a citizen's arrest.
Challenged by a woman, thought to be filming the incident, who says 'you said you want us dead', the grey-haired man shouts: 'I do want you dead!
'I want you dead right now!'
He goes to grab the driver, while a young boy was sits in the car, and shouts: 'You're under a citizen's arrest put your hands on the car.
'Get ready to die! You're under a citizen's arrest.'
Wheeling around and pointing at the family members he shouts: 'You're under a citizen's arrest, you're under a citizen's arrest, and I'll tell you what: you are too!'
Hampshire police confirmed officers attended and assault allegations were made but neither party wanted to pursue them so no further action will be taken.
Driver Simon Gale, 33, who was at the receiving end in the incident, told the Mail Online the man went into a 'raving state'.
He told the national newspaper: 'My son was so scared by it that he actually ended up sleeping in our room last night. He's very shaken.
'Luckily none of us are harmed in any way - but we're still quite shaken by it. We're definitely going to be a bit more cautious from now on.'
Mr Gale said he had been with his wife and son driving to Portsmouth on the day, with the video thought to be filmed near Hedge End.
A Hampshire police spokeswoman said: 'We were called to a non-injury road traffic collision on the M27 between junctions 5 and 7 at 11.30am on July 22.
'The incident involved a Mazda 3, a Peugeot 107 and a Skoda Octavia.
'When officers attended all parties had moved to the Sainsbury’s car park in Hedge End.
'A 32-year-old man from Southampton and a 54-year-old from Gloucestershire each made an allegation of common assault but neither party wanted to pursue the complaint.
'As a result, advice was given to both parties and they were told that two assaults will be recorded and filed.'