Police have defended their approach in dealing with protesters who blocked an M25 junction.

Campaigners from Insulate Britain blocked a section of the South Mimms M25 roundabout (junction 23) near to junction 1 of the A1 around 8am on Wednesday.

Multiple protesters sat themselves across the roundabout completely blocking access for drivers.

Hertfordshire Constabulary arrested 18 people following the protest and confirmed they have been released under investigation following liaison with the Crown Prosecution Service.

All 18 people are subject to Community Protection Notice Warnings.

The investigation is ongoing and further action will be taken pending further enquiries, the force added.

Chief Superintendent Richard Liversidge said comments have been made regarding the approach taken by officers.

One video clip showed an officer giving protesters their final warning before action would be taken.

Ch Supt Liversidge said: “I would like to remind people that what they are seeing is a very short clip, depicting an officer engaging with the group and informing them that if they did not move off the road, they were going to be arrested, in line with standard procedure.

“This resulted in 18 arrests being made yesterday and a full investigation is underway. We understand the frustration regarding the traffic delays experienced but would ask that people understand that we did – and are doing – everything in our power to deal with the situation.”

He added that officers were faced with a “challenging situation” in which protesters had blocked the carriageway and “glued themselves to the tarmac”.

He said: “Tasked with ensuring the safety of the wider public and those in the carriageway, they worked quickly to minimise disruption to motorists on the local and wider road network.

“Unavoidably, due to this group’s actions, it took time to safely de-bond the protestors from the tarmac as well as ensure that the roads could be safely re-opened.

“Policing protests is complex, in part due to the operating environment, the number of people involved and the need for us to deploy specialist resources to resolve and manage the situation.

“There are clear, national standards regarding the policing of a protest which our officers were following. The powers we have are created by Parliament, and we use them fairly and proportionately.”

Home Secretary Priti Patel is said to have called on police to crack down on the protests which brought traffic to a halt.

Ms Patel had already criticised the “selfish” protesters after they stopped thousands of motorists at four junctions on Britain’s busiest motorway on Wednesday for the second time in three days.

She added: “This Government will not stand by and allow a small minority of selfish protesters to cause significant disruption to the lives and livelihoods of the hard-working majority.”