A deputy constable is recovering in hospital after he was shot four times in the back in Houston, Texas, authorities have said.

Police Officer Shot

Alden Clopton was leaning into a patrol car, talking to a female colleague, when the suspect approached him from behind and opened fire on Wednesday night.

The 11-year veteran officer is expected to survive after undergoing several hours of surgery.

Authorities said the constable’s protective vest likely saved his life.

Deputy Clopton remains in critical care, a spokeswoman for the precinct told reporters on Thursday.

Constable May Walker said the shooting “was virtually an ambush”.

Police are questioning a “person of interest”, who turned up at a nearby fire station after the shooting.

Officials have not announced any arrests, but investigators are not currently looking for anyone else.

A motive for the shooting is unknown.

Constable Walker said the gunman fired six shots.

The female deputy got out and fired back, but it is not known if she hit the gunman, who fled on foot.

“She jumped out of the car and saw a guy running and got off one round,” Constable Walker said.

Deputy Clopton is married and has children. His three brothers who are also law enforcement officers.