Farm worker Stephen Morgan, 28, told a jury he had drunk eight pints before climbing into a 50-tonne bulldozer at Eppynt, near Sennybridge, Powys, during a protest against plans to bury animal carcasses.

Stephen Morgan denies the charge

Swansea Crown Court was told that Morgan had taken a DC Caterpillar from a contractors' compound on the Eppynt Mountain, near to the British Army ranges.

Officers were on duty nearby policing a demonstration involving hundreds of villagers.

The jury heard the heavy plant vehicle driven by Morgan hit a police personnel carrier "almost immediately" with PC John Stone inside.

But the defendant told the court the collision had not be deliberate.

Morgan, of Bronallt, Llandovery, has already admitted aggravated vehicle taking and dangerous driving, but denied attempted murder.

Pc John Stone: Terrified

He claimed he had no recollection of demolishing a road sign and fencing or hitting two portable cabins.

Morgan also said he did not notice he had run over a tent at an Army checkpoint.

The court was told that Morgan then began to descend a hill and the bulldozer hit a police transit van, pushing it down the road.

Morgan said that as he shunted the van, he he collided with the personnel carrier containing Constable Stone, who had to be cut free.

The defendant admitted crushing the van but said he had not realised at Pc Stone was inside at the time.

Police were called to deal with protesters

Morgan continued onwards, digging up the central reservation while officers tried to rescue Pc Stone, who escaped with just a broken ankle.

The defendant then veered off into a field before dumping the bulldozer and running to an empty farmhouse.

Then he swerved across a field before dumping the bulldozer and running off into a farmhouse, the jury was told.

When the occupants returned hours later they found him in bed, naked and asleep.

Judge Roderick Evans dismissed three of the 10 charges against Morgan.

Morgan denies attempting to murder PC Stone, damaging several vehicles and endangering life.