Nairobi: Gunmen executed at least seven people in Burundi’s capital hours hours before police launched house-to-house searches for weapons on Sunday, amid international fears of fresh bloodletting in the central African nation.

Hundreds of police and soldiers ringed the northern flashpoint neighborhood of Mutakura in the capital Bujumbura early Sunday to start of a widely feared crackdown on “enemies of the nation.”

Residents said security forces were carrying out house-to-house searches.

“The police started the search operation for hidden weapons in Mutakura,” city mayor Freddy Mbonimpa said, adding the raids were being “done professionally, because the police are using weapon detectors.”

The mayor said seven people were killed and two wounded in an “execution” attack adding that a probe had been launched to track the “assassins.”

International alarm has grown as a government amnesty ended to hand in weapons ended with fears that it will trigger further violence and drawing warnings from the head of the UN, Washington and the world’s only permanent war crimes court.

Gunmen late Saturday shot dead at least seven people and wounded two others in an attack on a bar in an opposition Bujumbura neighborhood.

Witnesses said attackers, wearing police uniforms, stormed into the bar, forcing those drinking outside to enter and lie on the ground before opening fire.

Burundi has been hit by waves of violence triggered by President Pierre Nkurunziza’s successful bid to change the constitution and win a third term in office, with bodies found dumped in the streets on a nearly daily basis.