MANILA - An Indonesian couple was behind the Jolo Cathedral blast that killed 23 people in January, the Philippine National Police confirmed Wednesday.

Authorities are also verifying reports that the children of the couple, identified as Rullie Rian Zeke and Ulfah Handayani Saleh, are in the Pilippines, said General Oscar Albayalde, the PNP chief.

"We want to thank yung (the) Indonesian government for helping us. Remember may mga (there were) Indonesian investigators that came here," Albayalde said.

• Several killed, dozens wounded in twin blasts at Jolo church
• Indonesia says married couple behind church bombing in Philippines

The mainly Muslim island of Jolo is one of the areas in the country's restive south where the Islamic State-affiliated Abu Sayyaf group operates.

The group, infamous for bombings, kidnappings and decapitations, has been classified by the Philippine government, as well as the United States, as a terrorist organization.

--Report from Raffy Santos; With Kyodo News