An American sea captain held hostage by pirates jumped into the ocean and tried to swim away, but he was retaken by the Somali bandits, military officials said.

WASHINGTON — An American sea captain held hostage by pirates jumped into the ocean and tried to swim away, but he was retaken by the Somali bandits, military officials said.

Capt. Richard Phillips, taken hostage when pirates tried to seize his ship on Wednesday, appeared to be unharmed after his escape attempt around midnight local time in the open ocean off the Somali coast, Defense Department officials said Friday.

The pirates are holding Phillips aboard a drifting lifeboat, with U.S. officials trying to negotiate his release.

After his recapture, Phillips could be seen aboard moving around and talking aboard the lifeboat, from the vantage point of a U.S. Navy ship patrolling nearby, said the officials, who spoke on condition of anonymity because they were not authorized to talk about the sensitive, unfolding operation.

Phillips, 53, was taken hostage aboard the enclosed lifeboat with four pirates who fled when his crew overpowered pirates trying to take their U.S.-flagged ship, the Maersk Alabama.

Negotiations are taking place between the pirates and the captain of the USS Bainbridge, who is taking direction from the FBI, the defense officials said. The destroyer arrived on the scene Thursday and is within sight of the lifeboat.

The bandits are communicating with other pirate vessels by satellite phone, officials said. Pirate vessels apparently were also heading to the scene to provide them backup.

The Navy is moving a huge amphibious ship closer to the scene of the pirate hostage standoff off Somalia.

Defense officials say the USS Boxer will be nearby soon. They spoke on condition of anonymity because they were not authorized to publicly discuss sensitive ship movements.

The Boxer is the flag ship for a multination anti-piracy task force. The Boxer resembles a small aircraft carrier.

It has a crew of more than 1,000, a mobile hospital, missile launchers and about two dozen helicopters and attack planes.

Two other Navy ships are expected to remain much closer to the pirate-held lifeboat. The USS Bainbridge is in sight of the lifeboat; the USS Halyburton is nearby. The Bainbridge uses drones to keep watch on the lifeboat. The Halyburton has helicopters.