A boat carrying 173 passengers overturned in rough waters in central Philippines on Thursday, killing at least 33 people. The boat, Kim Nirvana, was traveling from the central city of Ormoc to the island of Camotes, Agence France-Presse (AFP) reported.

Search and rescue operations began after the accident. But it was not immediately clear how many people died in the mishap as different media reports cite conflicting numbers. A report by GMA Network said that at least 34 people were killed and 70 people were missing after the accident. The report also cited a local news network, which reported that at least 60 people were rescued from the waters. The Associated Press reported that 36 people died, while AFP reported that 33 were killed.

Philippine Coast Guard (PCG) spokesman Cmdr. Armand Balilo said, according to GMA Network, that the rough sea caused the boat to overturn. The AFP report added, citing Ciriaco Tolibao from the city’s disaster risk reduction and management office, that at least seven rescue boats picked up dozens of survivors who were holding on to overturned hull of the capsized boat.

Last September, 70 people went missing after a ferry carrying 58 passengers and 25 crewmen capsized in the country off the coast of Southern Leyte province. The accident reportedly took place due to Typhoon Kalmaegi.