WEBSTER, Pa. — A gunman got out of his car during a late-night traffic stop and shot two police officers, one fatally, and law enforcement officials today are trying to track down the man they believe pulled the trigger, state police said this morning.

Police blocked off roads in the small town of Webster, south of Pittsburgh, today as they tried to serve an arrest warrant for the man they believe shot and killed East Washington police Officer John David Dryer late Sunday night.

Investigators identified the suspected gunman as Eli Franklin Myers, of Webster.

Investigators believe Myers stepped out of his van and opened fire on Dryer and officer Robert Caldwell after being pulled over shortly before midnight in Interstate 70 in Washington County, Trooper Joseph Christy said.

Dryer and Caldwell were both shot in the ensuing gunfight. Caldwell’s injury was non-life threatening, authorities said.

Officers surrounded Myers’ home about 25 miles south of Pittsburgh but could not say for sure if he was inside.

Emergency vehicles blocked off roads near Myers’ home near the town center of Webster, a small town on the east bank of the Monongahela River. The school district canceled classes while authorities tried to find Myers.