Nairobi, Kenya ? An American skipper held hostage by pirates tried to swim to freedom Friday but was recaptured seconds later when the bandits opened fire within view of a U.S. destroyer.

Four Somali pirates, who are demanding a ransom, were ready to kill Capt. Richard Phillips if they are attacked, according to a Somali in contact with the captors.

The high seas drama turned more complex and potentially deadly in its third day as both pirates and American forces rushed reinforcements to the scene several hundred miles off the coast of Somalia. The crisis stemmed from a thwarted attempt to take over the U.S.-flagged Maersk Alabama freighter and is testing the new Obama administration.

The pirates summoned reinforcements, calling in four commandeered ships with hostages from a variety of nations including the Philippines, Russia and Germany, according to the Somali in touch with the pirates.

The U.S. was also bolstering its force by dispatching other warships to the scene several hundred miles off the Somali coast, which already was under watch by the destroyer USS Bainbridge — named after William Bainbridge, an American naval officer who fought pirates off the Barbary Coast in the early 19th century.

Piracy along the anarchic and impoverished Somali coast, the longest in Africa, has risen in recent years. Somali pirates hold about a dozen ships with more than 200 crew members, according to the International Maritime Bureau, a piracy watchdog group based in Malaysia. The bureau lists 66 attacks since January, not including the Alabama.

Underscoring the high stakes involved, France’s navy freed a sailboat seized off Somalia last week by other pirates, but one of the hostages was killed, along with two of the bandits. Three pirates were captured. In Paris, Armed Forces Chief of Staff Jean-Louis Georgelin dismissed the notion that there was any coordination between the French and Americans on the two incidents.

Phillips, of Underhill, Vt., was seized Wednesday after he thwarted the pirates’ bid to hijack the Alabama, which was carrying food aid for hungry people in Somalia, Rwanda and Uganda.

Around midnight Friday local time, Phillips jumped off the covered lifeboat where he was being held and began swimming, said Defense Department officials, speaking on condition of anonymity because they are not authorized to talk about sensitive, unfolding operations.

One of the pirates then fired an automatic weapon, the officials said, although it was not clear if shots were fired at Phillips or into the air, and he returned to the lifeboat.

He was in the water only a matter of seconds — not enough time for sailors aboard the Bainbridge to do much to help him, the defense officials said. Because both the lifeboat and the Bainbridge are moving, no swimmers or divers could have been standing by in the water, the officials said.

The Bainbridge stays a minimum of 200 yards away — too far to send its own lifeboat to pick up the captain in just a few seconds, and it has no helicopter on board, they said.