BETHLEHEM, Pa. (AP) —Pennsylvania State Police say a corporal who was shot three times during a traffic stop has undergone surgery and is in “extremely critical” but stable condition.

Captain Richard D’Ambrosio says the trooper has made progress and “we’re hopeful that it will continue.”

The shooting happened Tuesday morning on a highway in Plainfield Township, Northampton County, about 65 miles north of Philadelphia.

D’Ambrosio says the trooper had stopped a motorist for speeding and called for backup when he suspected the suspect was intoxicated. He says the troopers were about to arrest the motorist when he began resisting. D’Ambrosio called it a “knock-down, drag-out fight” and said “it got very, very violent.”

The troopers exchanged gunfire with the suspect and shot him. Police say the suspect fled and drove himself to Easton Hospital, where he was taken into custody. He is being treated for gunshot wounds.

Police gathered evidence from suspect’s car, which appeared to have its rear window shot out.

The names of the trooper who was shot and the suspect were not released.

Gov. Tom Wolf tweeted that he is "praying for this trooper and their family."

More information will be released as it becomes available.