TULSA, Okla. (KFOR) – Authorities are asking for the public’s help after an Oklahoma police officer was injured in an assault.

On Feb. 7, a Tulsa police officer responded to an area in front of the federal courthouse after protestors blocked two lanes of traffic with their vehicles.

When the officer asked the protesters to move their cars and stay on the sidewalk, officials say the protesters said they “did not have to adhere to his instructions because he had no jurisdiction over them per the McGirt court case,” a post by the Tulsa Police Department read.

The group got louder and started to close in on the officer.

At one point, authorities say three individuals in the group started to assault the officer.

“The officer fell to the ground and the suspects surrounded him,” the post read.

Investigators say another protester stepped in and tried to get between the suspects and the officer. At that point, other officers arrived on the scene and deployed pepper spray.

The officer suffered a torn ACL, torn meniscus, and a fracture to the top of his tibia bone.

Authorities arrested Sandy Williams and Jacob Richard Nokysece Wind, and they will be charged in federal court.

However, a third suspect is still on the loose.

Photo of third suspect released by Tulsa police

If you have any information, contact Tulsa CrimeStoppers at (918) 596-COPS.