Police believe a man fatally shot his 11-year-old daughter at a Gwinnett County park over the weekend before turning the gun on himself.

An officer made the grisly discovery Saturday evening while patrolling Bethesda Park near Lawrenceville, Gwinnett police said in an emailed statement. Authorities said the officer was conducting a random check about 11:30 p.m. when he spotted a vehicle at the back of the parking lot.

As he approached the car, the officer discovered the body of 45-year-old Ignacio Ramos and his 11-year-old daughter, Valeria Ramos. Both had been shot at least once, police said.

“Investigators believe Ignacio killed Valeria before committing suicide,” agency spokesman Cpl. Collin Flynn said Tuesday. “Those detectives are continuing to work to identify a motive for this incident.”

Anyone with information about the case is asked to call Gwinnett police at 770-513-5300. Tipsters can remain anonymous, and be eligible for a cash reward, by contacting Crime Stoppers at 404-577-8477, texting information to 274637 or visiting the Crime Stoppers website.