NORTHAMPTON — After some three hours of drilling, grinding and cutting Thursday afternoon, police were able to free four anti-war protesters who had blocked the gates at L3Harris by securing themselves to a pickup truck filled with concrete.

The four — Joey Dehais, Sonya Epstein, Clara Wagner and Elin Dahal — were then arrested and charged with disturbing the peace, trespassing, resisting arrest and interfering with a police officer.

Dehais, identified as the driver of the truck, was charged additionally with a felony count of malicious destruction of property over $1,200 for allegedly backing into and damaging the sliding gate to L3Harris’ loading docks, Northampton Police Capt. Victor Caputo said.

The four were arraigned Friday in Northampton District Court and released on conditions.

Caputo said the protesters had welded steel to the early 2000s Toyota Tacoma and covered it with concrete. Specially trained State Police officers used drills to chip out the concrete and grinding and cutting tools to remove the steel.

The protesters were covered with blankets to prevent sparks from burning them, and the steel had to be watered down to keep it cool, Caputo said.

The protesters were using the sleeping dragon maneuver, which is designed to hinder their removal by anyone else, but from which they can release themselves if they choose.

“They refused to release,” Caputo said.

The truck was turned into scrap metal as police took off the roof and doors and cut through the back and bed, he said.

Caputo couldn’t say what the operation, involving numerous troopers, firefighters and local police, would have added up to in terms of man hours.