From the Archives, 1970: Vigilante unionists rampage at Werribee
In December 1970, a vigilante group of fifty trade unionists went on a rampage at Werribee, wrecking and burning thousands of dollars worth of equipment on a section of natural gas pipeline. The group were protesting the use of scab welders working on the project after it was black-banned by the union.
Source: brisbanetimes.com.au