Opposition to the Brighton bypass bridge over the Jordan River in southern Tasmania escalated after the April 12 decision by the Tasmanian heritage minister Brian Wightman to give final approval for works to proceed.
The bridge will destroy kutalayna, a site of 42,000 years of Aboriginal occupation.
On April 14, protesters entered the site and stopped the works. On April 15, 21 people were arrested after protesters scaled the fence and entered the site in waves, stopping the work on several occasions.