The U.S. Navy has sent a rescue and salvage ship to the Korean coast to aid in the recovery of the sunken ferry Sewol, the Korean defense ministry said Tuesday.
"Korea has requested the USNS Safeguard to participate in rescue operations and it is expected to arrive at the site of the wreckage on Friday," defense ministry spokesman Kim Min-seok said in a briefing.
Earlier in the day, Pentagon spokesman Col. Steve Warren also said that the ship is moving from Thailand to Korea to participate in the rescue efforts.
The 3,300-ton vessel is designed to conduct a variety of operations such as salvage, diving, towing, off-shore firefighting, heavy lift operations and theater security cooperation missions, according to the U.S. Navy.
It was also mobilized to provide assistance for tsunami-stricken Japan in 2011.
The Safeguard will be the second U.S. ship to help the Korean Navy and Coast Guard battling to find possible survivors from the ship that capsized off the country's southwestern coast on Wednesday with nearly 200 still missing out of 476 passengers.
Right after the ferry sinking, the U.S. Navy amphibious assault ship USS Bonhomme Richard has been engaged in search and rescue operations in the area of the sinking, some 20 kilometers off the coast of Jindo Island, South Jeolla Province.
"Helicopters from the Bonhomme Richard flew search and rescue operations yesterday," Warren said Tuesday.
A U.S. Navy engineer and master diver also were helping out aboard a Korean navy ship, he said.
Despite the fact that seven days have passed since the accident, authorities have not reached an official cause for the sinking of the ship.
The chief of the U.S. investigative agency for civil transportation accidents said it will help Korea to find the cause of the accident should an official request be issued from Korea.
"We always investigate accidents and try to find out what happened. There is not one cause of any accident. There are always multiple issues that need to be addressed," Deborah Hersman, the chairwoman of the National Transportation Safety Board, told the National Press Club in Washington D.C. on Monday.
"I have reached out to my counterpart in Korea. We will continue to support them if we are called upon."
In a question regarding the Korean authorities' handling of the accident, she said, "We are deferring to the Koreans and their leadership on the investigation. This is their vessel and an accord is within their purview."