A FEROCIOUS and unprovoked attack left a van driver shaking after his vehicle was forced into an emergency stop by his assailant, a court heard.

The attack on Robert Reed, 56, as he drove from York to Harrogate along the A59 and negotiated the Allerton Park roundabout, was witnessed by three police officers, Harrogate magistrates were told.

Fork-lift truck salesman Spencer Cassidy, 27, who denied affray and dangerous driving, was said by PC David Witts to have overtaken Mr Reed's white van on the roundabout, leaning out of his black Mondeo with his body visible down to the waist.

Prosecutor Sue Kerr said he had turned round to look back while still driving and making obscene gestures before 'stamping' on his brakes, leaving skid marks on the road.

He cut a 90-degree angle in front of Mr Reed's van, causing a following stream of traffic to have to brake sharply to avoid collisions.

PC Witts said Cassidy's manner grew angry as the incident, which began when traffic was held up by a slow-moving tractor, progressed.

Cassidy, of St Mark's Avenue, Harrogate, stopped and flung his car door open before storming back to the van, shouting.

In an unprovoked attack he unleashed blows through the open window as Mr Reed tried to defend himself.

Mr Reed, a delivery driver heading for his last drop of the day in Harrogate, said traffic was travelling at about 15mph when he reached the roundabout. He moved out, intending to pass the tractor, when Cassidy sounded his horn and he saw him waving his fist at him.

Three times after the overtaking manoeuvre Cassidy braked violently in front of him before finally stopping. "I saw the driver's door open. Cassidy came towards me saying 'What's your game?' and then threw punches through my open window".

Mr Reed said he covered his face with his hands to protect himself before his attacker was pulled off.

Cassidy said he drove 35,000 miles a year, mostly for his work, and was returning from a meeting in York.

Mr Reed cut in front of him on the roundabout and shook his fist at him when he sounded his horn.

Mr Reed continued to gesticulate at him and when he had to stop because of the tractor he got out to remonstrate with him.

"I can't remember what the flashpoint was but we exchanged a few swinging arms although no blows connected. Then I felt arms pulling me away and ceased all action."

After a seven-hour trial Cassidy was found guilty of both charges. Presiding magistrate Arthur Richards called for probation reports and adjourned the hearing until May 19. Cassidy was banned from driving in the meantime.