An investigation has been launched after disabled mother-of-two claims she was violently tackled to the ground by a policeman for no reason.

Karlene Raphael, who walks with two crutches after damaging her spine in a tram accident in the summer, was taking her 10-year-old son to Fieldway tram stop to go to school on Tuesday November 15 when she said the alleged incident took place.

A woman began arguing with her, and Miss Raphael said she gestured with her crutch for her to go away.

The 42-year-old from Dunsfold Way, New Addington, said: “I had seen a police car go by minutes earlier. She went over to make a complaint and I went over too.

"The policeman must have come from behind because before I knew it my legs were kicked away and I was knocked to the ground.

“He was lying on top of me shouting and my son was grabbing at him screaming get off my mum. People around where shouting at him to leave me alone that I had done nothing.

“Eventually he got up and just left. He didn’t even arrest me. My back was in agony. All I want is justice, a policeman is supposed to protect us.”

She claims the policeman also swore at her son and tore buttons off his school uniform during the struggle.

She said: “It was terrifying for him.”

Helped to her feet by passers-by Miss Raphael was taken to hospital with a swollen shoulder and is recovering at her flat with her son Rahieem and 3-year-old Toni.

Lodging her complaint on November 20, she received a letter from the Professional Standards Unit at Croydon Police Station on November 24 stating the matter was being investigated within the borough.

A police spokesman police said: "We can confirm that we received a complaint from a member of the public on 21 November 2011 regarding alleged excessive use of force by an officer in Croydon and this is currently being investigated by our Professional Standards Unit at Croydon."