Police are appealing for witnesses after an “appalling” mugging which left a woman temporarily blinded after a chemical was sprayed in her face.

The top layers of both the victim’s eyes were burnt off in the attack on March 4, police said.

After a Sunday afternoon shopping in Wimbledon, the 21-year-old victim was attacked on Tramway Path after exiting the Tramlink from Mitcham station.

She was stalked by two women who were also on the tram, one holding a water bottle filled with the chemical which was then used to spray her in the face and fall to her knees.

As her eyes burned, the thieves took her shopping bags and her purse, which contained £15 in cash, her bank cards and driving licence.

Despite her injuries the victim managed to phone 999 and call for help from the emergency services.

She was taken to hospital by the London Ambulance Service where she received immediate treatment.

Her eyes were burnt and her face was swollen from the unknown chemical and she had lost her vision.

She was released from hospital that evening but has to return regularly for further specialist treatment.

A medical examination showed the top layers of both eyes have been burnt off and, although the victim's eyesight is improving, medical treatment continues, police said.

Tests are still being carried out to determine what liquid was used in the attack.

Police are now appealing for any witnesses who saw the attack, and would be able to identify the suspects again, to come forward.

Detective Constable Simon Callcott, from the Metropolitan Police said: "This young lady has been subjected to an appalling and completely unprovoked attack which may result in her sight being permanently impaired.

“This type of attack is extremely rare and I would urge anyone who has any information to contact police.”

The first suspect is described as a light-skinned black female with long wavy hair, wearing a woollen hat and dark clothing including a jacket with a fur lined hood or collar.

Her accomplice is described as a light-skinned black female with long hair and a fringe, who was wearing a short black leather jacket and green tracksuit trousers with three white stripes down each side. She was also wearing a black scarf which she used to wrap around her head before the attack.

Anyone with information is should call police on 020 8649 4044 or Crimestoppers anonymously on 0800 555 111.

Police have arrested two people, who have been bailed pending further enquiries.

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