Around 50 protesters faced off against police at the entrance to a Co Antrim forest where an oil consortium is attempting to carry out exploratory drilling.
One man was arrested and several cars were towed away by police during the day-long stalemate, which saw the entrance to Woodburn Forest blocked by vehicles to prevent Infrastrata gaining access to start work.
Protesters have been camped outside the forest for 24 hours a day in icy conditions since learning that Infrastrata was planning to go on site on Monday. Throughout yesterday, local residents arrived to offer support and deliver sweets and pizzas.
Infrastrata wants to drill an exploratory well near Woodburn Reservoir, which supplies drinking water to Larne, Carrickfergus, Newtownabbey and large areas of Belfast.
The plan has proved unpopular, with more than 100 people attending a public meeting at the Windrose in Carrickfergus on Wednesday night, where Mid and East Antrim Mayor Billy Ashe refused requests for an extraordinary meeting to air concerns that Infrastrata is going on site without all the correct permits in place.
The council admitted a waste management plan had not yet been approved for the exploratory drill and that this process required a public consultation that had not taken place.
Yesterday, local residents were angered as police said they were suspending the public right of way into the forest, a popular spot for fishing, walking and horse riding.
Officers lifted the suspension later in the afternoon after a tractor and trailer blocking the entrance were removed.
Last night, protesters and police remained in place after contractors for Infrastrata ferried in concrete blocks and built a wall blocking vehicular access to the forest.
There were also raised eyebrows as one PSNI officer used bolt-cutters to detach a padlock placed on the gate by a protester. Campaigners claimed the police were aiding Infrastrata instead of upholding the law.
Campaigner Lisa Armitage had her car impounded after she used it to block the entrance.
"I jumped in the car and locked myself in to stop them moving me off," she said. "Eventually, they (police) got a hand in the door and said that I was obstructing the gate.
"I think it's disgraceful that they have got all these police here. They said they are here to enforce the law, but they are not being impartial."
Local resident Walter Johnston said he was angry at the way the deal had been pushed through without consultation.
"You need planning permission for a porch, but they can do this under permitted development rights, which isn't full planning permission," he added.
Fiona Joyce from the Stop the Drill campaign said Woodburn was a precious water catchment area and an amenity people love.
"Belfast City Council took a motion in September that there needed to be a review, but Mid and East Antrim Council have refused to consider it," she told this paper, adding that Mid and East Antrim Council has ignored representations from campaigners.
"There was a huge crowd of people calling on the council mayor last night to convene a special meeting this morning and he refused," she said.
Dr James Orr, NI director of Friends of the Earth added: "One person said to me, 'we can live without oil but we can't live without our water' and I think that sums it up. What disturbs me is that this is publicly-owned land that was acquired by NI Water to protect as a water catchment, and they have leased it to a company that could seriously risk our drinking water supplies."
Police said they arrested a man in his 50s in connection with a protest at the forest.
Chief Inspector Stephen McCauley added: "As a police service, we respect the rights of people to protest, as long as it is within the law."
A Mid and East Antrim Council spokesman said the proposed borehole exploratory drilling fell under permitted development rights.
"The removal of trees does not fall within the definition of development and therefore does not require planning permission," he added.
NI Water said a clause in its agreement with Infrastrata prohibited fracking and that it was satisfied the work would have no detrimental impact on the reservoir or the public water supply.
A spokesman added there is no formal public right of way in Woodburn Forest, but NI Water has always been happy to permit recreational access.
Infrastrata has insisted its methods are safe and that the water supply and surrounding area will be protected.