The Australian state of Victoria, which includes Melbourne, has made at least one vaccination dose mandatory for all construction workers by the end of the week.
According to officials, construction sites were also being noncompliant with other key health and safety requirements before they were shut down.
The construction industry in Victoria has been linked directly to 403 direct Covid cases in recent weeks.
Victorian health minister Martin Foley said: “As a result of these figures, the public health team was left with no choice but to hit the pause button.”
The construction workers were also joined by anti-vaxxers and those against the prolonged lockdown in Victoria.
Protesters then crowded around the CFMEU (Construction, Forestry, Maritime, Mining and Energy Union) building in high-vis clothing while setting off flares earlier this week, ignoring the stay-at-home orders.
The crowds were furious their union had not backed them up in their fight against obligatory vaccines.
As demonstrators gathered, an officer from the line of riot police told the crowd: “Attention, this is a police public order warning.
“You have previously been directed to leave. Leave now or force may be used. No further warnings will be given.”
More than 60 protesters were arrested after damaging property, blocking a freeway and injuring officers.
Officers used pepper balls, foam baton rounds, smoke bombs and stinger grenades with rubber pellets throughout the eight hours of protests.
Shane Patton, police commissioner of Victoria state, said: “This was a very, very large and very, very angry group.
“And it was a challenging and confronting environment.”
Protests also took place on Monday, when there were approximately 500 demonstrators. However, according to CFMEU construction secretary John Setka, most of these Monday crowds were “rightwing extremists” pushing back against mandatory jabs.
He told ABC: “There was a small minority of construction workers, some of them when it all got violent just walked away from it. It was hijacked by the professional protesters.”
Explaining why the industry had been shut down, industry and transport minister Tim Pallas said: “The construction industry is effectively amplifying and spreading the virus into communities, particularly in the north and the west of Melbourne, but also the south-east and then back into other workplaces.”
He added that this week’s protests showed “some appalling behaviour on our streets”, which added up to a “public health risk”.
Sites will have to prove they are compliant with health measures and all workers will have to have at least one dose of vaccine before they can reopen in October.
The public were advised to stay away on Wednesday.
Australia has already locked down its largest cities – Sydney and Melbourne, along with the capital Canberra – following an outbreak of the Delta variant.
On Tuesday, Victoria reached its highest daily figure for Covid infections at 603, although Australia’s infections have still remained much lower than many other comparable nations.