As backup officers arrived, the sergeant said, "Get me an address, the lieutenant's been shot," according to the police.

The fighting then spilled to the sidewalk as backup officers arrived.

The officer who had been shot fired two rounds before backup officers arrived.

At that point, two of the three backup officers rushed in and opened fire, the police said.

No shots were fired by the backup officers, who had rushed up too late to be directly involved.

To protect the witnesses, the detectives called for backup officers to make the arrest.

Minutes later, the backup officers found the detectives on Hannah Street.

Over the radio, the backup officers heard him knock on a door, and then heard no more from him.

The officer followed him to the street, where he alerted backup officers on the street.

By that time, the four backup officers, from Transit Unit 12, were approaching the scene.