Manila: The death toll in twin bomb blasts outside Roman Catholic Church Cathedral in Southern Philippines rose to 27 from 19 on Sunday. 77 others are left wounded in the incident.

The national police chief of the country Oscar Albayalde confirmed the death toll and revealed that the first bomb went off in or near the cathedral at Jolo island during a Sunday mass. Adding, he claimed that the second explosion occurred outside the compound as government forces were responding to the first blast.

The deceased include five troops and three civilians. No terror organisation has immediately claimed the responsibility of the attacks.

Photos of the incident site, doing rounds on social media, showed debris and bodies lying on a busy street. As a security measure, the troops have sealed off the main road leading to the Cathedral of Our Lady of Mount Carmel.

Troops in armored carriers sealed off the main road leading to the church

Jolo island has long been troubled by the presence of Abu Sayyaf militants. The US and the Philippines have blacklisted Abu Sayyaf as a terrorist organisation because of several incidents of kidnapping, bombing and beheading.

“I have directed our troops to heighten their alert level, secure all places of worships and public places at once, and initiate pro-active security measures to thwart hostile plans,” said Defense Secretary Delfin Lorenzana in a statement.

The attack came nearly a week after minority Muslims in the predominantly Roman Catholic nation endorsed a new autonomous region in the southern Philippines in hopes of ending nearly five decades of a separatist rebellion that has left 150,000 people dead.