A Baltimore County police officer was shot to death Wednesday during a predawn raid on a house in Catonsville, police said. His alleged assailant was also killed in the firefight.

Officer Jason Schneider, 36, a 13-year veteran of the force, was trying to capture a suspect wanted in connection with a shooting last week in the same neighborhood, police said. He turned a corner in the home and met a hail of gunfire.

Schneider was the first Baltimore County officer killed by gunfire in 13 years.

Alleged shooter Tevon Smith, 25, died later Wednesday at Maryland Shock Trauma Center, police said.

Smith, who lived in the house in the first block of Roberts Avenue in Catonsville, was not the person Schneider and other officers were seeking, police said.

Baltimore County Police Chief James W. Johnson fought back tears as he spoke of Schneider, a married father of two whom he described as a leader in the department's tactical unit.

"This is a terrible loss for Baltimore County," he said.

Officers were serving warrants to search the house on Roberts Avenue and arrest a 16-year-old suspect in an Aug. 19 shooting on Winters Lane. That suspect remained at large Wednesday night, police said.

Other people who were inside the home were taken to police headquarters to be interviewed.

Johnson said the raid followed "an extensive tactical briefing and much planning."

County Executive Kevin Kamenetz called it "a well-prepared police event."

"Officer Schneider was killed in the line of duty, and we deeply mourn his loss," Kamenetz said. "I can only tell you that we don't always appreciate what our police do for us every day, but it's times like this when we know how grateful we are for their bravery and their sacrifice."

Gov. Martin O'Malley ordered the Maryland state flag flown at half-staff.

The ill-fated operation began at daybreak, when a team of officers entered the white clapboard house on Roberts Avenue.

As Schneider and other tactical officers entered the home, people began to flee. Johnson said the occupants clearly realized that the officers were police. At least one person was armed.

As Schneider turned a corner inside the home, police said, he was shot multiple times.

A preliminary investigation showed that his vest stopped several rounds, but one round traveled under his vest and struck him in the back.

Johnson said Schneider, who a colleague said was a former Marine, managed to return fire and struck the suspect several times.

Another officer also fired his weapon, police said. That officer was to be placed on administrative leave pending the investigation.

Police were trying to determine the source of the weapon used in the shooting, Johnson said.