Militants in India-held Kashmir killed one officer and wounded three paramilitary troops in an attack on a police facility early on Saturday, police said. Indian forces returned the attack.

The militants detonated grenades and fired automatic assault rifles to gain entry to the district police headquarters in southern Pulwama district, which also houses families of some officers, director general of police S.P Vaid said.

One police officer was killed in the initial assault and three paramilitary troops were injured who were evacuated to a nearby hospital, he said.

“Two more CRPF (Central Reserve Police Force) soldiers died” in pursuit of the attackers, Vaid told AFP.

“We are evacuating the families from there,” he said.

It was not clear how many attackers were inside the compound.

Government forces have stepped up counterinsurgency operations since the start of the year and have killed at least 136 separatists, including most of the top commanders of militant groups operating in the the disputed territory.

Kashmir has been divided between India and Pakistan since the end of British colonial rule in 1947. Both claim the territory in full.

Militant groups have fought the more than 500,000 Indian soldiers deployed in the restive territory for decades, demanding independence or a merger of the former Himalayan kingdom with Pakistan.

Tens of thousands, mostly civilians, have died in the fighting.