Five people, including two children, are dead and a suspect is on the loose Saturday after a late-night dispute between neighbors escalated into an “almost execution-style” killing in Texas, authorities say.

38-year-old Francisco Oropeza was firing a rifle in his yard late at night when his neighbors asked him to stop, San Jacinto County Sheriff Greg Capers said. The man then went next door with his with an AR-style gun, opened fire and killed five people, including an 8-year-old and a 15-year-old, authorities said.

Capers said “everyone that was shot was shot from the neck up, almost execution-style.”

He also said some of the victims appeared to be protecting children.

Authorities were using scent-tracking dogs and an overhead drone to search for Oropeza on Saturday after police say he fled toward a wooded forest a few miles away.

As the search dragged into the evening, authorities had widened their efforts to as far as “10 to 20 miles” from the murder scene. He said Oropeza may still have a weapon but that he believes authorities have the rifle used in the shooting.

Capers said they found clothes and a phone while combing a rural area that includes dense layers of forest but that tracking dogs had lost the scent.

“He could be anywhere now,” Capers said.

The shooting occurred overnight in the town of Cleveland, about 45 miles north of Houston.