MANILA, April 3 (Xinhua) -- An improvised bomb exploded Wednesday afternoon in the southern Philippine province of Sultan Kudarat, injuring at least six civilians, a military spokesman said.

Colonel Gerry Besana, the spokesperson of the military's Western Mindanao Command, said the explosion occurred at around 3 p.m. local time near a roadside restaurant in a town named Isulan in Mindanao.

No other details were available as government security forces rushed to the scene to investigate.

"An explosive ordnance team is now patrolling the vicinity," Besana said, adding that "all military checkpoints were ordered to implement strict measures" to track down the perpetrators.

The victims were rushed to a hospital for treatment, he added.

No group claimed responsibility for the attack.