US Navy Ship May Not Be Salvageable As It Continues to Burn (+Video)

The fire on the USS Bonhomme Richard in San Diego is still burning but firefighters have made "significant progress" toward putting it out, a Navy admiral said Tuesday.

According to AP, the Navy officials were able to inspect four main engineering rooms and found no major damage, and the external structure of the ship appears to be safe, said Rear Adm. Philip Sobeck, the commander of the strike group whose flagship is the USS Bonhomme Richard.

But he cautioned at a briefing that there is still "a major fire inside" being fought by hundreds of sailors who were focusing their efforts on two isolated spots near the stern and the bow of the ship. It was unclear if there were two distinct fires on board or if the area burning near the tail end was simply from the heat of a single large blaze, Sobeck said.

It's also unclear whether the amphibious assault ship that is akin to a mini-aircraft carrier can still be repaired.

The fire temperatures had reached up to 1,000 degrees (538 Celsius), causing the mast to collapse and threatening the central control island where the captain operates the vessel.

Helicopters had dumped 1,200 buckets of water on the ship, allowing crews to move further on board to fight the blaze. Tugboats were assisting from the waterline.

The fire spread rapidly from the front to the rear of the ship and quickly ballooned into one of the worst Navy shipyard fires in years. It could cost the military an estimated $4 billion to replace the ship. At least 61 people, including 38 sailors and 23 civilians, have been treated for heat exhaustion, smoke inhalation and minor injuries. None were in the hospital Tuesday.

Maritime lawyer Rod Sullivan, who served in the Navy, said two separate fires on a ship is highly unusual and could raise questions as to whether arson was involved.

"It is very, very difficult for fire to traverse the entire length of ship," and then to not cause damage in every compartment, said Sullivan, who has handled fire cases involving everything from large passenger ships to yachts. "Arson has to be considered as a possibility here."

Sobeck said the fire appears to have traveled upward to an open hangar-like area and from there, fueled by oxygen, it raced along the ship's ventilation and cables, causing it to traverse the ship. Cables and duct work being done as part of the ship's maintenance fed the fire and later created barriers to sailors trying to fight it.

Also, at least two fire-suppression systems were not able to be used. One was deactivated while the ship was being worked on, and the other was not able to be launched because of an explosion — believed cause by pressure building up when the fire started, Sobeck said.

CNN also reported that the Coast Guard is preparing for an oil or other hazardous waste spill but there is currently no discernible sheen on the water to indicate a spill, said Coast Guard Capt. Timothy Barelli.