Philippine security forces killed eight Muslim rebels Thursday as they hunted the remnants of a guerrilla force hiding in homes of a major city and believed to be holding hostages. A soldier also died, the military reported, bringing the death toll from 11 days of fierce street battles in the southern port city of Zamboanga to at least 114. The fresh casualties came as an international human rights monitor issued a report alleging severe human rights abuses committed by both sides, including the rebels deliberately picking out Christians to use as human shields. \"Both sides need to do all they can to prevent further loss of civilian life,\" Human Rights Watch Asia director Brad Adams said. Hundreds of Moro National Liberation Front (MNLF) gunmen entered Zamboanga, a major southern trading centre with one million residents, on September 9 in an effort to derail negotiations aimed at ending a decades-long Muslim insurgency. Three military brigades, or about 4,500 soldiers, have been deployed to neutralise the rebels, according to national military spokesman Lieutenant-Colonel Ramon Zagala. But the rebels have frustrated the military efforts and prevented a full-out assault by hiding in residential neighbourhoods and holding residents hostage. The military said the rebels may still be holding about 25 civilians. Nevertheless, the military has pledged to kill or capture the rebels unless they surrender. Eight more rebels were killed in fierce firefights on Thursday in the city\'s Santa Barbara neighbourhood, one of two areas where the rebels are holed up, local military spokesman Captain Jefferson Somera said. The military has given varying estimates of how many rebels are believed to still be holding out, from 30 to 70. It has reported killing 94 rebels and detaining another 93. It said the fighting has also left 13 members of the security forces as well as seven civilians dead. The civilians included a two-year-old boy who had been among the civilians used as human shields by the rebels, and a six-year-old girl hit by a stray bullet at an evacuation centre. Human Rights Watch detailed one incident on the third day of the conflict in which it alleged the military shot repeatedly at a group of rebels who were using Christian hostages as human shields. \"The shooting was relentless,\" it quoted one survivor, Monica Limen, as saying. It said Limen\'s 20-year-old son was killed in the crossfire. The watchdog also alleged that the security forces had tortured or otherwise mistreated detained rebels. Military spokesman Zagala denied soldiers had fired at hostages, or committed other abuses. \"If there are human shields we refuse to fire. If we had not been following this policy this fight would have been over a long time ago,\" he told AFP. \"We don\'t tolerate violations of human rights.\" About 113,000 people are in government shelters after being displaced by the fighting, according to official figures, and Zamboanga continued to be paralysed by the conflict. However flights in and out of the city\'s airport resumed for the first time on Thursday. Muslim rebels have been fighting since the 1970s for an independent or autonomous homeland in the south of the mainly Catholic Philippines. An estimated 150,000 people have died in the conflict. The MNLF signed a peace treaty in 1996 that granted limited self-rule to the south\'s Muslim minority. However MNLF founder Nur Misuari deployed some of his men to Zamboanga to show opposition to a planned peace deal between the government and the remaining major Muslim rebel group, the 12,000-strong Moro Islamic Liberation Front. The MILF is close to signing the peace pact, which Misuari believes would sideline the MNLF.