Tasmania's forest wars look set to reignite following news 'spiked' timber has damaged sawmilling equipment.
Potentially fatal bolts were allegedly discovered driven into logs at two Tasmanian logging mills in the Derwent Valley and at Bridgewater.
Karanja Timbers have alleged two bolts were driven into logs from Sustainable Timber Tasmania's Wentworth coupe.
The company said the bolts broke a saw which will cost at least $3,000 to replace.
Police are now involved and the Bob Brown Foundation has denied any of its activists are responsible.
Terry Edwards, chief executive of the Forest Industries Association of Tasmania says it is extremely dangerous.
"This is a deliberate act and the bolts haven't been there long. There is no blue on the wood where the bolts have been - this is very recent," he said.
He says it's very fortunate workers weren't hurt.
“This incident could have severely injured or killed these workers and this is an extremely serious situation."
While, Greens leader Cassy O’Connor has backed the Bob Brown Foundation.
She says she's highly suspicious that this is another attempt to blame and demonise people who are standing against forest destruction.
“The Tasmanian conservation movement has a long and proud history of peaceful protest. It has never resorted to tree spiking,” Ms O’Connor said.
"The last time tree spiking was alleged, in 2012, it was found to be the work of a disgruntled industry worker."
"We support the calls from environmental groups for a full Tasmania Police investigation of the alleged incident at a Tasmanian logging mill. That investigation must include contractors and employees of the businesses involved," she added.