Watch more in iWantv or TFC.tv

MANILA - The Metro Manila police on Monday raised full alert after twin explosions in a church left dozens killed and injured in Jolo, Sulu.

The full alert status means the police will intensify its checkpoints, patrols, coordination with the military, and intelligence gathering with other agencies, said the region's police chief, Director Guillermo Eleazar.

Policemen were also directed to cancel any work leave, he told radio DZMM.

The first bomb at the Jolo Cathedral exploded Sunday as Mass was being celebrated. As troops rushed to help the wounded in the heavily damaged church, a second bomb went off in the parking area, the military said.

The bombing killed at least 20 people and injured 112 others, including 3 children, according to command incident spokesperson Faghry Ukkoh.

The bloodshed came less than a week after a majority of voters approved a new region giving Muslims in the south more control over their own affairs, which sparked hopes of quelling long-time separatist violence.

Sulu voted against creating the new region, but the area will still be part of the Bangsamoro because voters from across the current autonomous region voted in favor of it on the whole.

The military on Sunday said it believes that Abu Sayyaf bandits could be behind the fatal explosions.

"We will not allow them to spoil the preference of the people for peace," National Security Adviser Hermogenes Esperon said. "Peace must prevail over war."

With a report from Agence France-Presse