According to Maj. Filemon Tan, spokesman for the military's Western Mindanao Command, the troops were on security patrol when they clashed with an undetermined number of Abu Sayyaf fighters in Barangay Tugas.
He said the bandits were under Abu Sayyaf sub-leader Hairullah Asbang.
The Abu Sayyaf faction in Sulu is holding dozens of hostages including 14 Indonesian and four Malaysian tugboat crewmembers abducted in three incidents off Tawi-Tawi.
The group is also holding two Canadians, a Norwegian and a Filipina abducted last September at a resort in Samal island in Davao del Norte.
The kidnappers are demanding P300 million each for the two Canadians and the Norwegian and have given April 25 as deadline.
Military officials said operations are ongoing to rescue the captives.
Sulu is a stronghold of the Abu Sayyaf, a small but violent al Qaeda-linked group known for beheading, bombings and extortion activities. —KBK, GMA News