An undetermined number of Filipinos claiming to be members of the Sultanate of Sulu have been killed while there have been no Malaysian casualties, The New York Times reported.
The village of Kampung Taduo in Sabah state where the gunmen are holed up was bombed and strafed by Malaysian aircraft in advance of a ground assault, Malaysian Defense Minister Ahmad Wahid said.
The group of about 200 people, calling itself the Royal Army of Sulu, landed in the remote Malaysian village of Lahad Datu by boat from the southern Philippines Feb. 9. Its members have for weeks resisted pleas from both Kuala Lumpur and Manila to return to the Philippines.
In previous clashes, Malaysian forces claimed to have killed 27 members of the group.
The Filipino clan had earlier allegedly killed eight policemen in Borneo. It also reportedly lost 19 of its members during the three-week stand-off.
Jamalul Kiram III, one of 11 claimants to the title of sultan of Sulu, said Tuesday in Manila his supporters in Borneo would "fight to the last man protecting their ideals and aspirations."
Malaysian naval forces remained on alert as armed groups in southern Philippines had threatened to counterattack Sabah's east coast if Tanduo came under fire, the Philippine Star reported.
The report said the Malaysian government had earlier warned the intruders they had only until midnight Feb. 26 to leave Lahad Datu peacefully.
The current government in the Philippines is involved in a peace process with Islamic militants in the southern Philippines, which is home to Islamic militant groups.
The government of Philippines President Benigno Aquino III Monday urged Malaysia to use great restraint in dealing with the current situation.
The BBC reported Malaysia may be asked to allow a Filipino naval ship to sail to Lahad Datu to bring the clan members home.