A former detective told a Court he did not spark a road rage incident but was trying to chase a dangerous driver.

Former officer Andrew Kennedy claimed motorist Robert Stell had forced his teenage son's bike into the kerb and then deliberately knocked another cyclist over during an incident in Ilkley last April.

"If I hadn't taken any action at all I wouldn't have been doing my duty as a police officer - whether on duty or off duty,'' Kennedy told District Judge (Magistrates) David Thomas.

Kennedy, who was a detective constable, retired from the police force on medical grounds in December last year after suffering an injury on duty.

He has pleaded not guilty to causing an estimated £1,500 of damage to Mr Stell's Honda Legend car and a further charge of disorderly conduct.

The prosecution at Bradford Magis-trates Court alleged that Kennedy, who had been taking part in a bike ride with fellow cyclists, smashed his bicycle twice onto the bonnet of Mr Stell's car during a confrontation in New Brook Street.

Kennedy said yesterday: "It's my practice not to get involved in incidents with motorists unless I really need to."

Describing the incident, he said: "The car reached the junction and without braking or without slowing down just shot out of the junction without any regard for anybody else on the road.

"He cut the corner and turned right and drove very quickly up New Brook Street. The whole time his engine was revving and his tyres were screeching... it was like a getaway driver.''

Kennedy said he went after the driver on his bike with the intention of getting his registration number, and was able to catch up with him at a set of traffic lights which were at red.

"I got to the side of the car and tapped on the window and said, 'I'm a police officer. You've driven into two cyclists. Stop','' he said.

Kennedy then went between the front of the white car and another vehicle, intending to stop him from moving off.

"The engine was revving loudly and he was driving towards me. I jumped out of the way because I thought he was going to pin me into the back of the car in front.''

Kennedy claimed it was then he decided to put his bicycle on the bonnet of the car to prevent the driver leaving. He denied he threw his bike down.

He tried to grab the car keys because he feared Mr Stell might try to drive off.

He denied being angry and said he had been "very determined'' to get the registration number.

The trial continues.