LOS ANGELES, Sept. 11 (Xinhua) -- With the body of the final victim of the boat fire off the California coast last week recovered by the divers, the search operation ended on Wednesday.

The Santa Barbara County Sheriff's Office announced the end of the search on Twitter, saying it was "relieved to report" the final victim had been found.

DNA testing is still being conducted to confirm identities of seven of the 34 victims, according to the sheriff's office.

The U.S. Coast Guard announced earlier Wednesday it has issued new safety recommendations in the wake of the fatal boat fire.

The agency recommended limiting the unsupervised charging of lithiumion batteries and the use of power strips and extension cords.

The bulletin also suggested that owners and operators of vessels review emergency duties with the crew, identify emergency escapes, check all firefighting and lifesaving equipment onboard, and look at the condition of passenger accommodation spaces for "unsafe practices or other hazardous arrangements."

Salvage operations to raise the dive boat Conception out of the water restarted Tuesday, after several days of weather delays, said Santa Barbara County Sheriff Bill Brown.

The 34 victims included 21 women and 13 men, aged from 16 to 62, according to authorities.

Brown said the preliminary examinations indicated the victims died of smoke inhalation and perished before they were burned.

Authorities are still working to identify the victims and release their remains to their families.

The cause of the boat fire has not been revealed yet. Federal authorities have launched a criminal investigation into the dive boat fire.

The U.S. Department of Justice on Monday confirmed that it was participating in the joint investigation with the Coast Guard, the Federal Bureau of Investigation, the Bureau of Alcohol, Tobacco, Firearms and Explosives, and the Santa Barbara County Sheriff's Office.

Possible ignition sources include the electrical system, photography equipment, batteries, cameras and phones that were plugged in and charging when the fire broke out, according to the U.S. National Transportation Safety Board (NTSB).

The NTSB will release a preliminary report in 10 days on the cause, and a final report could take one to two years to release, said NTSB member Jennifer Homendy.

The 34 victims were thought to be sleeping below deck when the boat was engulfed by fire. Five crew members on deck survived by jumping into the water, and were later rescued.

The boat carrying 39 people was on a three-day diving trip when the 23-meter-long, three-story commercial diving vessel erupted into flames and sunk off the Santa Cruz Island in southern California On Sept. 2.