HOUSTON (NewsNation Now) — Police arrested a suspect, after a Houston officer was killed in the line of duty, but they’re still looking for a person of interest.

Houston Police Chief Art Acevedo had a message Monday for the person who shot one of his officers:

“We are going to catch you, we are coming after you, we are going to capture you. So do yourself a favor and turn yourself in,” he said. “We have leads.”

Acevedo said the incident started at 1:35 p.m. CST when someone called police reporting shots fired.

Officers arrived five minutes later, but the Houston police veteran of 25 years would not survive.

Acevedo identified the officer as 47-year-old Sgt. Sean Rios. He said Rios had “engaged the suspect in a gunbattle,” for unknown reasons and was shot while outside his car. Rios tried to run into a nearby motel office but collapsed and died.

Rios was allegedly on his way to his shift at the police department and was not in uniform.

Rios leaves behind four children and two cousins who are also in the Houston Police Department.

Acevedo said this is the department’s fourth line-of-duty death since Dec. 7 of last year — three of those deaths were by gunfire and one was a helicopter crash. One of those deaths was last month when a 41-year veteran of the force, Sgt. Harold Preston, was killed responding to a domestic call.

The chief said they believe the shooter was in a four-door, blue Mercedes. They have taken that vehicle into evidence. Acevedo said they believe the shooter is a Hispanic man in his mid to late 30s, with multiple tattoos.

Police are also looking for a black pickup truck possibly connected to the incident.

Acevedo said the area where the shooting occurred is busy — near a major interstate — and emphasized they have leads.

“If you are rendering assistance to this individual […] you are committing a crime, so have them turn themselves in,” said Acevedo.

Houston Mayor Sylvester Turner implored the public for help in solving this case.

“It’s not just up to HPD to solve these crimes,” he said. “If you know something, it’s vitally important for you to say something.”

Anyone who has information about this shooting can contact Houston Crime Stoppers.