THIS is the shocking moment students scream out in terror as a classmate is bitten by a police dog after a mass brawl broke out at a Sheffield school.

Dramatic footage shows the dog sinking its teeth into the student as three cops try to drag it off.

As the pupil struggles on the ground outside Fir Vale School, a girl can be seen being pinned to a car bonnet during the clash today.

Cops were scrambled to the mass brawl after the fight spilled on to the street.

Social media pictures showed a line of police cars outside the school, which had to shut early following the fight between pupils.

One witness said: “We drove past and all hell was breaking loose.

"We saw two police riot vans and police dogs. We saw parents and pupils trying to climb over the fences.

"I'd say there were about 100-150 people rioting and there was chaos on both sides of the fence.”

Dramatic footage showed police breaking up fights on the road outside the school gates.

A spokesman for South Yorkshire Police told the Sun Online: “At around 12.55pm this afternoon police were called to Fir Vale School on Owler Lane, following reports of an altercation between a group of students.

“Officers were deployed and on arrival found that a large number of people had gathered at the gates.

“The crowds have now dispersed and officers remain in the area, liaising with the school.”

Yorkshire Ambulance Service said two patients were treated at the scene with minor injuries.

Headteacher Simon Hawkins said: “An incident in school has meant we closed today at 2pm. All pupils are safe.

“Any child who should not leave early will be supervised on site in our library."

In February this year the school was evacuated when a car crashed into the front entrance at the height of the morning run.

Nobody was injured but the school was closed for the day.