HOUSTON (AP) — A sheriff's deputy in uniform was shot and killed Friday night while filling up his patrol car at a suburban Houston gas station, according to authorities.

The unidentified deputy was pumping gas into his vehicle when a man approached him from behind and fired multiple shots, Harris County Sheriff's Office spokesman Ryan Sullivan told The Associated Press. Once the deputy fell to the ground, the suspect fired more shots.

Police said they have a description of the male suspect, who was driving a red or maroon Ford Ranger truck, and have begun an intensive search.

The identity of the sheriff's deputy was not immediately released, but he was a 10-year veteran of the force.

Sheriff's office spokesman Deputy Thomas Gilliland said the officer had traveled to the Chevron station where the shooting happened, after earlier responding to a routine car accident.

"He was pumping into his vehicle . and the male suspect came up behind him and shot the deputy multiple times," Gilliland told the Houston Chronicle (http://bit.ly/1JCEswB ). "The deputy fell to ground. the suspect came over and shot the deputy again multiple times as he lay on the ground."

He said the officer died at the scene. Detectives were checking security camera video for possible clues.

"We are actively searching for suspect right now," Gilliland said, describing the males suspect as about 5-foot-10 to 6-feet tall, wearing a white T-shirt and red shorts. "I can tell you with diligence and justice the suspect will be caught. And he will be brought to justice ... This is a very callous individual."

Harris County Sheriff's deputies and homicide investigators joined officers from other agencies, including the Texas Department of Public Safety and the Houston Police Department, in searching for the suspect.

"This is a very tough moment right now for the Harris County Sheriffs Office," Gilliland said. "Keep us in your prayers and in your thoughts."

"Bob Goerlitz, president of the Harris County Deputies Organization, said the incident was "shocking."

"We've been warned of things like this, because of public sentiment nationally and events over the last few years ... It's just horrific. That's the only way to describe it."