US cargo ship captain Richard Phillips has been rescued from pirates after a dramatic shootout.

Mr Phillips was freed unharmed but the US military killed three Somali kidnappers who were holding him hostage on a lifeboat, according to reports. A fourth pirate is in custody.

Initial reports said the sailor jumped overboard before a gunfight broke out between his captors and US Navy Seals.

US President Barack Obama gave authority to kill the pirates, and a commander acted when he concluded the pirates were about to kill the hostage, a US Navy official said.

Mr Phillips has now contacted his family, received a medical evaluation, and is resting aboard the amphibious assault ship USS Boxer.

His ship the Maersk Alabama, a container carrying food aid for Somalians, was attacked far out in the Indian Ocean on Wednesday, but its 20 American crew apparently fought off the pirates and regained control.

Crew members said Mr Phillips volunteered to go with the pirates in a lifeboat in exchange for safe passage for his crew.

Maersk Line chief executive John Reinhart said in a statement: "We are all absolutely thrilled to learn that Richard is safe and will be reunited with his family."

The crew of the Maersk Alabama let off flares and hoisted an American flag at the news of their captain's rescue.

One crew member shouted: "We are very happy. He's a hero" at journalists amid raucous celebrations.

Mr Phillips, 53, was the first American taken captive by Somali pirate gangs who have marauded in the busy Gulf of Aden and Indian Ocean shipping lanes for years.

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