The Philippine army special forces and police killed 13 suspected criminals in a fierce shootout on Sunday, the latest violence in the country reviving calls for tighter gun controls.

The gunmen, believed to be members of a gun-for-hire group, opened fire from two black SUVs on more than 50 army soldiers and police officers when authorities tried to pull the three vehicles over at a highway checkpoint in the coastal town of Atimonan, in Quezon province. The third vehicle fled the scene.

Eleven died at the scene while two others taken to a nearby hospital were pronounced dead, Quezon provincial police chief Valeriano de Leon told AP.

“They rolled down their windows and started fighting, so we had to retaliate,” Lt. Col. Monico Abang, who led the army platoon in the clash said, adding that the men were likely involved in illegal drugs, gambling and kidnapping for ransom.

Sunday’s shooting followed a tip from a source who said that the gunmen would pass through Atimonan in the northeast province. Authorities secured the site of the checkpoint following the shootout, which lasted for 20 minutes.

The dead include a police colonel who was a regional commander and two other officers, said police spokesman Erwin Obal.

The incident sparked stronger calls for officials to impose stricter gun controls and crack down on unlicensed weapons in the country where the proliferation of firearms has long been said to have fuelled crime.