AN ALLEGED road rage incident caused a road to be closed on a busy Hampshire bypass after a collision left five injured.

Police are now investigating an alleged assault by one driver on another as well as the cause of the crash on Western Way, Fareham, yesterday afternoon.

Police are today waiting to question a driver after a headbutting allegation.

Both drivers were hurt in the crash and from the subsequent alleged assault witnessed by scores of people in the consequent traffic jams.

Both cars were travelling south on to Western Way from the A27 slip road fly-over from the M27 when a silver Skoda Felicia estate was involved in a collision with a red Peugeot hatchback after overtaking on hatched road markings.

The Skoda hit and mounted the central reservation and rolled over on to its wheels, ending up slewed across one lane of the opposite northbound carriageway with a broken windscreen and all the panels and roof crushed.

One of the drivers, a 40-year-old man from Titchfield, was taken to Queen Alexandra Hospital, Cosham, along with his 39-year-old wife and a six-year-old girl, both passengers in his car. The driver had suspected back injuries and a cut forehead, the girl had shock and the woman back injuries.

The woman got out of the Skoda and collapsed on the verge. Meanwhile, the Peugeot driver walked from his damaged car on the other side of the road and approached the Skoda driver.

An assault then took place, claimed onlookers and the victim, who made an allegation to police.

The Peugeot driver was treated at the scene by paramedics. Two ambulances took him, his wife and the little girl home to Titchfield.

The accident and alleged attack happened at about 2.30pm, causing massive traffic chaos for about two hours when cars were stopped from using Western Way in both directions and the fly-over.

Investigators photographed and sketched the crash scene and the police spotter plane circled overhead photographing the site.

Eye witness Roy Maber, managing director of RMA Advertising, whose offices overlook the crash site, said: "I was standing outside in the car park when I heard this massive bang and saw the top of the Skoda turning over and over behind the landscaped mound.

"I saw a woman get out of the Skoda and collapse on the grass. The driver in a red shirt was out of the Skoda and another person helped the little girl out of the back seat.

"A man in a green shirt was lying on the ground, then he got up and walked down the road towards the other car.

"Then other people said something happened between them, but I didn't see anything.''

A police spokesman confirmed the Skoda overtook the Peugeot on the hatched road markings and a collision followed and that an allegation of an assault had been made by one of the drivers against the second.

PC Gerald Baker, of Fareham traffic police said: "After the crash an incident happened between the two drivers.

"We are urging witnesses to come forward to help us investigate an alleged assault and the crash.''

Witnesses are asked to contact Fareham traffic police on 0845 0454545.