US, French and Haitian firefighters used sonar, cameras and dogs Monday in the search for victims at a collapsed Haitian school, but as the stench of death rose from the wreckage, they no longer expected to find anyone else alive. Three days after the concrete building suddenly collapsed during a children's party, killing at least 94 students and adults and severely injuring 150 more, Capt. Michael Istvan of Fairfax County, Va., said the chance of more survivors was remote. He also said the death toll won't likely go much higher. Several bodies were pulled out Monday, caked in concrete dust, and radar and cameras located several more. But there have been no indications of survivors since four children were pulled from the wreckage Saturday morning, said Daniel Vigee, head of a Martinique-based French rescue team. Rescuers were probing spots where neighbors claimed to have heard voices or received cell phone calls from trapped survivors, without success. Finally, before dawn Monday, they opened up new areas to search by tearing down a two-story high concrete slab that had been hanging precariously since the collapse. Istvan's firefighters were flown in by the U.S. Agency for International Development, and an eight-person military team from the U.S. Southern Command also helped. They had warned that removing the wall could be too dangerous to rescuers and any potential survivors, but Haitians removed it anyway using hand-held power tools as hopes dimmed. It was unclear how many people were in the building when it collapsed, though the school is believed to have had about 500 students. Haitian officials said some had time to escape when it began to fall, and it was not known how many were pulled out unharmed on Friday. Some students weren't at the school during the collapse because La Promesse was holding a party requiring a donation 25 gourdes (63 cents) that poorer families could not afford, said Deputy Steven Benoit, who represents the area in the Chamber of Deputies. "A lot of students had their lives saved because they couldn't get in," Benoit said. The tragedy at the school - built along a ravine in a slum below a relatively wealthy enclave near Port-au-Prince - has brought more attention to chronic poverty in Haiti, where neighborhoods rise up in chaotic jigsaws and building codes are widely ignored. President Rene Preval has made several visits to the disaster site, blaming the collapse on constant government turnover and a general disrespect for the law. "There is a code already, but they don't follow it. What we need is political stability," Preval told the AP. More than 1.8 million of Haiti's 9 million people, according to one lawmaker's estimate, live in ramshackle slums that blanket mountainsides with squalid homes, shabby churches and poorly constructed schools like the one that tumbled down Friday. Anger and frustration over the painstakingly slow pace of the rescue effort has boiled over. On Sunday, about 100 people rushed the wreckage and began trying to pull down the massive concrete slab. Thousands of onlookers cheered them before Haitian police and U.N. peacekeepers drove them back with batons and riot shields. The school's owner and builder, Protestant preacher Fortin Augustin, turned himself in to authorities Saturday on charges of involuntary manslaughter, police spokesman Garry Desrosier said. Minister of Justice and Public Security Jean Joseph Exume said the case was still being investigated but the owner could face up to life in prison. Neighbors said they have long complained that the three-story school concrete block building was unsafe, and people living nearby have been trying to sell their homes since part of it collapsed eight years ago. "You can see that some sections just have one iron (reinforcing) bar. That's not enough to hold it," said 55-year-old Notez Pierre-Louis, who pulled her children out and sent them to a less expensive school. "I said all the time, one day this is going to fall on my house." Houses immediately below the school were destroyed in the collapse. Pierre-Louis' home, farther down the hill, was spared.