Xinhua Asia-Pacific news summary at 1605 GMT, Dec. 3

MANILA -- An explosion occurred inside a gym of Mindanao State University in Marawi City, Lanao del Sur province in the southern Philippines on Sunday morning, killing at least four and injuring 50 others, local military and police said.

The blast occurred past 7 a.m. local time when students and teachers gathered for a Catholic mass inside the gym, according to local police.

Major General Gabriel Viray,