Police are hunting a man who subjected a woman to a terrifying sexual assault after offering her a lift in a cab.

The smartly-dressed man offered to drive the 52-year-old woman home but instead drove to a car park by Brooklands Park, off Western Road, Lancing.

After being assaulted in the car, which had a taxi sign on the roof, the victim managed to escape on foot.

Shortly before the attack, the woman stopped outside a Salvation Army shop in South Street, Lancing.

Two women briefly spoke to her before the car pulled up.

Detective inspector Nigel Brown said: "The woman was extremely traumatised by the assault.

"We are anxious to trace the two women who spoke to the victim outside the Salvation Army shop.

"I am also appealing for anyone else who has information regarding the matter to get in contact including anyone who saw the victim in South Street or the vehicle in Brooklands Park.

"From the description of the vehicle and driver that has been given, I believe someone will recognise them. If they do, it is vitally important they contact us and report their suspicions."

The attacker was in his 40s, 5ft 9in, clean shaven and of smart appearance. He had a mark on the left side of his neck and a flabby waist.

He was wearing black trousers, a green V-neck jumper over a white-collared shirt and black shoes with zigzag-style stitching.

He also had a mobile phone with silver casing on the front.

The car was dark blue with four doors and silver alloy, spoked wheels.

On the roof above the front passenger seat was an oblong sign with an orange front with what was believed to be the word 'taxi' on it in black letters.

No taxi radio or meter was seen in the vehicle.

The victim, who is from Lancing, received medical care and is being looked after by specially-trained officers.

Mr Brown said: "I fully understand such offences cause increased concern to members of the community using public transport or travelling alone in taxis or private hire vehicles but I must emphasise such attacks are extremely rare."

He advised people to check they were getting into a correctly-licensed taxi or private hire vehicle, which should have local council-issued plates fixed to the rear.

Anyone with information about the incident on Saturday at 9.15pm should call 0845 6070999.