Malaysian police said Sunday two officers were injured in shootouts with Filipino gunmen as they try to end a month-long incursion in remote Sabah state that has already left 61 people dead.
Fifty-three militants and eight police officers have been shot dead since a group of armed Filipino Islamists landed in the state on Borneo island last month to resurrect long-dormant land claims of a self-proclaimed Philippine sultan.
Malaysia, facing its worst security crisis in years, insists the gunmen must surrender unconditionally, but the men have refused to lay down arms, hiding within a security cordon around two villages, palm oil plantations and swamp.
Sabah police chief Hamza Taib said gunmen have traded fresh fire with security forces since late Saturday with shots hitting two officers who were sent to a hospital in Sandakan town for treatment.
He also said six more people have been arrested in the state under a security law and are being investigated for "committing terrorist acts", bringing the total held under the law in relation to the crisis to 85.
Authorities stopped three boats near the battlezone Saturday and detained 27 people claiming to be fishermen. But it is unclear if any of them were included in Hamza's figure.
Meanwhile, authorities are fine-tuning operations in a "special security area" along Sabah's east coast, where they are stationing five army battalions, or about 3,500 men, to protect more than 1.4 million people following the incursion.
The crisis has embarrassed the Philippines and Malaysia, shining the spotlight on the latter's porous shoreline and locals' complaints of rampant illegal immigration and lawlessness.
About 235 people took part in the mission to reclaim the state for the sultan, a self-proclaimed heir to the former southern Philippine sultanate of Sulu, according to his people.
The intruders had been holed up in a farming village since February 12 before deadly clashes led Malaysian authorities to launch air- and groundstrikes on their hide-out.
Fears have also been raised of a wider infiltration by other gunmen or sympathisers already in Malaysia following a shootout in a coastal town, several hours by car from the battlezone.