Raw video,Octobe21/08:Tasmania,Australia,TENSIONS over the logging of old-growth forests in Tasmania have boiled over into a violent attack by timber workers, caught on video yesterday.

The timber workers are seen attacking a protest car with a sledgehammer and kicking in its windows as they demand that the occupants get out.

With increasing fury, more workers join in the attack, surrounding the car, which was deliberately disabled on a logging road, and leaving it trashed.

A 22-year-old man was dragged from the vehicle and kicked repeatedly, but was not sufficiently injured to need hospital treatment, said Ula Majewski of the group Still Wild Still Threatened.

The car, with its wheels removed, was blocking a road in the Upper Florentine Valley, the scene of repeated forest protests over the past two years.

The group disrupted logging in the area last week, costing contractors an estimated $10,000 in lost revenue.

Yesterday morning, one of the activists hid nearby with a video camera to capture the minute-long attack.

"I've f---ing warned ya," one of the men says. "Get out of my f---ing way, you bastards," he begins, as blows from the sledgehammer rain on the vehicle.

The attack subsides when the first attacker walks away and orders others to get equipment to push the car off the track.

Ms Majewski said the attack would be reported to police.

The Tasmanian Forestry Contractors Association's executive director, Ferdie Kroon, said the contractor involved recently had been through "absolute hell" personally.

"It's just boiled over in absolute frustration," Mr Kroon said. "These illegal protesters flout the law and get away with it. Unless the Government takes decisive action, this will get worse."

Forestry Tasmania spokesman Ken Jeffreys said protesters should take any allegations to police. He said a forestry official visited the site yesterday, but it was quiet at the time.