The number of confirmed dead in a California warehouse fire rose to 33 Sunday as investigators continued searching the burned out structure for human remains and evidence of a cause for the blaze. 
Some of the victims were foreign nationals from Europe and Asia, said Alameda County Sheriff's Sergeant Ray Kelly. 
He declined to say what countries the victims were from, but said authorities were working through diplomatic channels to identify them and inform their families. 
Only about 40% of the building has so far been searched, and Kelly said he had no idea how many more bodies might be found. 
"We expect the worst and are hoping for the best," he said, adding that some of the victims were teenagers. 
Complicating the recovery effort was the collapse of the building's roof and parts of the second storey. 
Oakland Mayor Libby Schaaf said the current focus of emergency teams was the "humane and compassionate removal" of the victims. 
The blaze was reported late Friday night during a party in a warehouse in Oakland, on the eastern side of San Francisco Bay in northern California, which housed artists and their studios as part of a collective. 
Survivors described the fire as an inferno, saying that chaos broke out in the building after the blaze erupted, according to Oakland Deputy Fire Chief Mark Hoffmann. 
People cried for help from the second storey where they were trapped, he said. 
Fire department officials said there was no sprinkler system in the building and no smoke detectors, and a stack of wooden palettes arranged as a provisional staircase was the only way out for people stuck upstairs. 
Known as the Oakland Ghost Ship, the complex was zoned as a storage facility, and conditions there had come to city authorities' attention before, according to news reports.

Source: QNA