Twenty five people died after a diving boat caught fire off the coast of Santa Cruz Island, north of Los Angeles, according to a U.S. Coast Guard official speaking to the Associated Press.

The 75-foot commercial vessel called the Conception, carrying 33 passengers and six crew, went up in flames at about 3:30 a.m. Monday, officials said.

After original reports that at least eight people were killed in the fire, Coast Guard Lt. Cmdr Matthew Kroll told the AP Monday night that 25 people had died.

Five crew members, who were awake and above deck on the bridge of the ship, jumped off and were rescued by a “good Samaritan” recreational vessel, U.S. Coast Guard Capt. Monica Rochester said earlier.

Initially four bodies were recovered from the scene, and four more were found on the ocean floor but could not be immediately recovered, Santa Barbara County Sheriff Bill Brown said in an afternoon news conference Monday.

Thirty-four of the 39 aboard the boat were sleeping below deck when the fire broke out, Rochester said.

The Conception, operated by Truth Aquatics out of Santa Barbara, was in full compliance with safety and licensing standards, she added.

Sheriff Brown said the timing of the fire and the ship’s location contributed to the tragedy, with flames breaking out as almost everyone on board was sleeping.

“To be in a remote location, have a fire that occurs, have limited if any firefighting capability that could address … you couldn’t ask for a worse situation,” he said Monday.

The vessel sank to the ocean floor about 20 yards from the shore four hours after the fire started.

So far, there’s no immediate evidence of a criminal act, authorities said.

Santa Barbara County officials said Monday the cause of the incident is under investigation and names of the victims are being withheld pending notification of kin.