(NewsNation) — A search is underway in Texas for the gunman who allegedly “ambushed” and killed an on-duty deputy Wednesday night, authorities said.

Sheriff Ed Gonzalez identified 44-year-old Ronnie Palmer as a person of interest in the “capital murder” of Harris County Sheriff’s Deputy Fernando Esqueda.

Esqueda, a five-year veteran of the sheriff’s office, was a member of the Violent Person Task Force.

“We pray with Deputy Esqueda’s family, friends, and colleagues during this incredibly difficult time. Deputy Esqueda’s commitment to duty and his sacrifice will always be remembered,” Gonzalez wrote. He said the suspect came into the location to pick up a pizza he ordered but got upset when his order was incorrect.

During a news conference Thursday, Harris County Sheriff’s Office Chief Deputy Mike Lee said deputies responded to an aggravated assault at a Little Caesars around 10 p.m. on Wednesday, according to ABC News.

Lee said the suspect allegedly verbally assaulted an employee before pistol-whipping them with a gun and leaving. The employee called the police and provided details about the getaway car.

Esqueda eventually spotted the suspect’s car and informed another detective over the phone that he had located the vehicle, Lee added.

While on the phone, “our deputy apparently was ambushed” and shot multiple times, Lee said.

Esqueda was rushed to the hospital, where he died from his injuries.

Anyone with information regarding Palmer’s whereabouts should contact Crime Stoppers of Houston at 713-222-8477.