Ambush sparked Sabah assault Ancient feud: Malaysian police detain men in eastern Sabah during a search for Filipino militants. Filipino gunmen allegedly mutilated several Malaysian policemen and beheaded one of them, three days before Malaysian security forces launched air and ground assaults against a group of militants in eastern Sabah. A group of 19 policemen were ambushed and six killed in the clash in a village near the coast town of Semporna last Saturday. Malaysian authorities have released only scant details about the incident, which shocked authorities and was the catalyst for Prime Minister Najib Razak deploying seven battalions of soldiers to Sabah with orders to use whatever force necessary to defeat the militants, informed sources say. More than 200 gunmen, claiming to be a royal militia in the service of the Sultanate of Sulu, arrived in Sabah, a Malaysian state on Borneo island, three weeks ago, claiming to be the rightful heirs of the area, prompting the most serious security crisis in Malaysia in decades. Many are still holed up in palm oil plantations 150 kilometres from Semporna, near the town of Lahad Datu. The sultanate was an Islamic kingdom that for centuries ruled the southern Philippines and parts of what is now Malaysia's Sabah state, but is not recognised by any state. The policemen were patrolling in the village of Simunul, two kilometres from Semporna, on Saturday night when they were ambushed. Several were tortured and their bodies mutilated, and one was beheaded, the Borneo Insider reported. It is against our religion to behead anyone. It's terrible, it's cruel," Azmi, a fisherman who lives near the village, was quoted as saying. About 50 police reinforcements were sent to the area and killed six militants in a fierce firefight, but others escaped, local media reported. The subsequent air and ground assault by Malaysian forces has killed at least 13 of the nearly 200 militants, Malaysian police officials said on Wednesday. At least 40 people have now died since the incursion began. Sporadic fighting continued on Wednesday in remote coastal areas as the police and soldiers scoured rugged territory, searching house-to-house to find rebels who escaped the assault on Tuesday. "The mopping and searching will cover a wider area given there are signs the intruders moved to another location," Ismail Omar of the Malaysian National Police told reporters, without providing further details. Extremist groups in the insurgency-plagued southern Philippines have often beheaded their enemies, including captured Philippine soldiers and kidnap hostages whose family did not pay a ransom. The gunmen who arrived in Sabah appear to be hardened fighters adept at insurgency tactics, raising the possibility of links with insurgency groups such as the Moro National Liberation Front. Last year Malaysia brokered a peace deal between the Philippine government and another group, the Moro Islamic Liberation Front, but the MNLF has not signed. The MNLF's leader, Nur Misuari, told journalists on Tuesday his group had not supported the incursion, but he warned Malaysian authorities not to harm Filipino civilians in Sabah. "Do not touch our civilians," he said. Once you do that, that will be tantamount to declaration of war against our people and the Moro National Liberation Front. "We are hurt and many of our people, even the non-combatants, are going to Sabah to help the sultanate," Mr Madjahab said. There have been no reports of more Filipinos arriving on Sabah, which is only an hour by boat from the southern Philippines. with The New York Times