Police will maintain an ongoing presence at East West Link drill sites in Melbourne as protesters vow to continue their "campaign of disruption".
Scuffles broke out between police and protesters for the second time this week when workers tried to commence drilling for the road project on Wednesday morning.
Officers forcibly removed demonstrators as they pulled down the protective fence around the hydraulic drill.
Acting Assistant Commissioner Rick Nugent says police will shuffle their resources and reassign officers to drilling sites over the coming days.
"We've seen about 60 to 80 police rostered to work at these protest sites," Mr Nugent said.
"Because we don't get full warning of the protest activity, we are having to take people off the front line."
The protesters have accused police of using heavy-handed tactics during the clashes.
Police said they would review footage to ensure officers acted within their mandate.
One protester, Rosie Elliot, said police targeted her while she tried to pull down the fence and her leg "might have been fractured".
No one was arrested on Wednesday but work at the drill site was abandoned due to safety concerns.
Organiser Mel Gregson said protesters would return on Thursday morning to continue their "campaign of disruption".
"What we showed is that no matter how many police the government deploys we can still disrupt and delay the work because we have the support of the community," Ms Gregson said.
"This community has a proud record of stopping inappropriate developments. The East West Link will be no different."
