The distraught mother of a 16-year-old mixed race boy said police pinned him to the ground and threatened to “f**king smash his face in” during what she believes was a racially motivated attack.

Herts Advertiser: Images of the alleged wounds. Picture: SuppliedImages of the alleged wounds. Picture: Supplied (Image: Archant)

She has questioned why the officer involved is still working while he is under investigation for the incident.

Lisa Kingston, who lives in Hatfield, cannot understand why her son - who is a student at Oaklands College in St Albans - was allegedly chased by police and threatened with violence.

Fortunately she has the whole incident on camera after a nearby WiFi salesman videoed the arrest on his mobile phone.

The woman says that her son was chased and forced to the ground on Stockbridge Road, Hatfield, by a Herts police officer who put his foot on the 16-year-old’s neck, pinning him in place.

Herts Advertiser: Images of the alleged wounds. Picture: SuppliedImages of the alleged wounds. Picture: Supplied (Image: Archant)

In the video, the officer then says: “Let go of my hand or I will f**king smash your face in, do you understand?!”

The boy begs a member of the public to stay with him as he is threatened with pepper spray and continually shouted at while being held down on the pavement.

Her son was then taken into custody and strip-searched, where he was found to have nothing on him. He was released without charge.

He was held in Hatfield police station from approximately 3pm on Tuesday, July 14 until 1.30am on Wednesday.

The boy complained of backache to the custody staff as he has a history of scoliosis, which was treated by Great Ormond Street Hospital when he was a child.

Lisa received a call from police while she and her partner were shopping in the local branch of Asda. They told then about the arrest and the couple subsequently went down to Hatfield Police Station to help their son.

When Lisa later presented her video footage of the long and drawn-out arrest, the sergeant she spoke to said he had been stopped for “looking suspicious” and on suspicion of stealing a motorbike.

No such motorbike was found and the heartbroken Hatfield mother says she has no idea where any of this “suspicion” came from as her son has no criminal record.

Lisa said: “I do believe this was a racist attack.

“He is covered in bruises. We are very frightened that this officer is still serving although the incident has been referred to the Independent Office for Police Conduct, the body for monitoring misconduct.”

The former Onslow St Audrey’s student was actually about to start a course in public services in September - the study of police, fire and ambulance services. But he now says he does not want to work for the police as he believes it is an environment which is institutionally racist.

Lisa has subsequently been told that the officer responsible for restraining her son is still continuing his duties. She said she and her partner have seen him outside their home three times since the incident.

This newspaper contacted Hertfordshire Police for a comment, and a spokesperson said: “Hertfordshire Constabulary has made a referral to the Independent Office for Police Conduct with regards to an arrest in Hatfield earlier this week.

“The original incident occurred when uniformed officers on patrol saw a male acting suspiciously on Tuesday, July 14. The male made off then was pursued and an arrest was made.

“A 16-year-old was arrested on suspicion of drug possession with intent to supply and assaulting a police officer with intent to resist arrest. He was released under investigation.

“It would be inappropriate to comment further at this stage.”