The crew of an American-operated ship hijacked by suspected Somali pirates early Wednesday has regained control of the vessel, but the pirates have taken the captain hostage, news agencies and television stations are reporting.

Ken Quinn, the second officer, told CNN in an interview that the pirates had taken Captain Richard Phillips captive on the ship's lifeboat. The crew took a pirate hostage in an attempt to negotiate a swap, but Quinn said that effort failed and the crew gave back the pirate.

Pentagon officials are saying four pirates attempted to take control of the ship off the Somali coast. A Pentagon official told the New York Times that other details remain murky.

The Maersk Alabama, a 17,525-tonne vessel, is crewed by 20 United States nationals and was on its way to Mombasa, carrying 400 containers of food aid.

John Reinhart, the chief executive officer of the U.S. firm which owns the ship, said at a noon EDT (16:00 GMT) press conference Wednesday that the company had received a phone call from the Maersk Alabama, and the crew reported that it was safe. Reinhart gave no other details, and refused to confirm or deny that the crew had regained control of the ship. Reinhart added that the company first heard the ship was taken at about 12:30 AM EDT (4:30 GMT).

Earlier, Robert Gibbs, the White House spokesperson, said that President Barack Obama and other U.S. officials were monitoring the situation and exploring all available options. "Our top priority is the personal safety of the crew members on board," Gibbs said.

The ship's home port was Norfolk, Virginia, and it was owned and operated by by Maersk Line, Limited in the United States.