25 dead in Beirut building collapse January 16, 2012 -- Updated 1840 GMT (0240 HKT) Rescuers search for survivors in the rubble of a collapsed building in Beirut's Ashrafiyeh neighbouhood on January 16, 2012. A six-story building collapsed Sunday night 25 people have been pulled from the rubble An investigation is under way Beirut, Lebanon (CNN) -- At least 25 people are dead after a six-story building collapsed in Beirut, the country's news agency reported Monday. The collapse occurred Sunday night in the Ashrafieh neighborhood of Beirut, NNA reported. All hospitals in the region were ordered by the Health Ministry to be prepared to take in the injured. The cause of the collapse was not immediately known and an investigation, led by Prime Minister Najeeb Mikati, is under way. The dead included Lebanese nationals, as well as people from Egypt, Sudan, Jordan and the Philippines, NNA reported. CNN's Nada Husseini contributed to this report.