POLICE have appealed for dash cam footage of a car seen travelling in the wrong direction towards the M2 before a five-vehicle crash in which one man died.
The PSNI said it received several reports "of a silver car travelling in the wrong direction on the M3 from the Sydenham bypass towards the M2" on Sunday afternoon.
They were working yesterday to establish where the vehicle joined the M3 and its movements prior to the collision.
Five cars were involved in the pile-up on the southbound carriageway near Duncrue shortly before 4pm, which left one man dead and three others injured.
The name of the man who died had not been released last night.
Those injured have since been discharged from hospital.
Witnesses described the scene of the crash as "horrific" with emergency services launching a huge rescue operation involving scores of firefighters and medics as well as the Air Ambulance.
Reports have suggested it was a female driver travelling in the wrong direction, with several witnesses giving their accounts on social media.
One man said: "The car was seen driving at high speed straight at incoming cars."
Another said: "She just missed us, I had to swerve out of the way."
PSNI Inspector Andrew Wilson said: "At approximately 3.50pm yesterday, Sunday 22 July, police received several reports of a silver car travelling in the wrong direction along the M3, Belfast, from Sydenham bypass towards the M2.
"We are working to establish where this vehicle joined the M3 and its subsequent movements prior to the collision.
"I would appeal to anyone who has dash cam footage of this vehicle or information relating to this incident to contact the Collision Investigation Unit at Sprucefield."
He added: "I also wish to express my thanks to the members of the public who have already come forward and provided us with dash cam footage and witness accounts leading up to this road traffic collision."
Meanwhile, the father of an eight-year-old boy killed in a road crash in Co Down on Saturday remained in hospital last night.
Callum Morrow from Lurgan died at the scene of the two-car collision on the Aughnacloy Road.
He is understood to have been returning home from a day trip to Newcastle with his father Stephen and six-year-old brother James when the tragedy happened.
His brother was discharged from hospital yesterday, but his father remained in a stable condition.
The condition of the woman who was travelling in the other car remained unknown last night.
The young boy was a pupil at Carrick Primary School and had just recently celebrated his First Holy Communion.
In a separate crash in Co Down yesterday, the Air Ambulance was sent to the scene of a collision involving a motorbike on the Newry Road, Kilkeel.
The crash happened shortly after 1pm. One person was taken to Daisy Hill Hospital in Newry by ambulance and a second was airlifted to the Royal Victoria Hospital with serious injuries.
