TOKYO/WASHINGTON (UPDATE)- All 20 Filipino crew members on board a Philippine-flagged merchant vessel that collided with a US Navy destroyer Saturday are safe.
Nippon Yusen KK, which charters the Philippine-flagged ACX Crystal, said this hours after the pre-dawn accident, which left at least three US sailors injured and seven missing.
The Japanese firm also said the cargo ship was not leaking oil after its bow hit the warship on its right or starboard side.
In a statement, the company said it would "cooperate fully" with the Japanese Coast Guard's investigation of the incident.
In Manila, the Philippines Department of Foreign Affairs said it was closely monitoring the incident.
"We are coordinating with the relevant authorities including the governments of the US and Japan to determine exactly the extent of damage and the number of casualties, especially if any Filipino nationals are involved," the foreign office said in a statement Saturday afternoon.
At around 29,000 tons displacement, the ship is about three times the size of the U.S. warship USS Fitzgerald and was carrying 1,080 containers from the port of Nagoya to Tokyo when the collision occured.
The U.S. Navy said in a statement that the warship, an Aegis guided missile destroyer, collided with the merchant vessel at about 2:30 a.m. local time (1730 GMT), some 56 nautical miles southwest of Yokosuka, a rare incident on a busy waterway.
Three aboard the destroyer had been medically evacuated, including the ship's commanding officer, Cmdr. Bryce Benson, who was reportedly in stable condition after being airlifted to the U.S. Naval Hospital on the Yokosuka base, the Navy said.
The other two injured were transferred to the hospital for treatment of lacerations and bruises, it said. The Fitzgerald, the Japanese Coast Guard and Japan's Maritime Self-Defense Force were searching for the seven missing sailors.
Benson took command of the Fitzgerald on May 13. He had previously commanded a minesweeper based in Sasebo in western Japan.
The waterways approaching Tokyo Bay are busy with commercial vessels sailing to and from Japan’s two biggest container ports in Tokyo and Yokohama.
International maritime rules for collision avoidance do not define right of way for any one vessel, but provide common standards for signaling between ships, as well as regulations on posting lookouts.
The USS Dewey and two Navy tugboats had been dispatched to provide assistance to the damaged destroyer, the Navy said.
Japan's public broadcaster NHK showed aerial footage of the ship, which had a large dent in its right, or starboard, side. Images broadcast by NHK showed it had been struck next to its Aegis radar arrays behind its vertical launch tubes.
The images showed what appeared to be significant damage on the deck and to part of the radar. NHK also showed footage of the container vessel and said it was heading towards Tokyo under its own power.
Such incidents are rare.
In May, the U.S. Navy's USS Lake Champlain collided with a South Korean fishing vessel, but both ships were able to operate under their own power.
The 7th Fleet commander, Vice Admiral Joseph Aucoin, thanked the Japanese Coast guard in a post on the fleet's Facebook page, adding: "We are committed to ensuring the safe return of the ship to port in Yokosuka."