A POLICE officer has been disciplined for driving at speeds of up to 140 mph - after being reported by the criminal he was transporting.

The police constable was driving the prisoner from Leeds back to Darlington when it is claimed he drove a marked police car at up to twice the legal limit.

It is understood the PC was reported by his passenger when the pair arrived at the custody suite at Darlington police station.

According to a source, the officer and the criminal during the 70-mile journey the pair discussed  the powerful BMW's performance.

The source said: “The conversation turned to the vehicle they were travelling in. Apparently the prisoner asked how fast it would go and the officer said something along the lines of ‘I’ll show you’ or ‘let’s see’.

“As soon as they got back to Darlington the prisoner proceeded to tell the officer at the custody desk just how fast they had been going on.”

Superintendent Darren Ellis, head of professional standards and legal services at Durham Constabulary, said the force had taken the allegation “very seriously”.

He added: “We are aware of this complaint, which concerns an allegation of a marked police vehicle being driven at an excess, and inappropriate, speed whilst transporting a prisoner back from Leeds into our force area.

“There were no other reports from members of the public reporting the police vehicle being driven at high speed, or dangerously.

“The PC in question has been moved permanently from roads policing duties, has been handed a formal sanction under the police misconduct procedures and is subject to an action plan concerning risk management and decision making.”

Supt Ellis said the officer’s licence has been suspended, including removing his pursuit capabilities.

The PC will also have to go through a driving school reassessment before returning to full operational duties.

The make and model of the speeding police car is not known. However, Durham Constabulary uses BMW 330D, 530D, X3 and X5 vehicles all capable of 140mph.

The law allows police, ambulance and fire service drivers to exceed the speed limit - but only in emergencies.