The ship and its crew of 21 were taken over Thursday off the Somali coast as the vessel headed for Kenya.

The Los Angeles Times reported Sunday that the pirates have warned against any raids by U.S. or Russian forces. Both nations have war ships responding to the crisis.

Pirates operate with relative freedom in and around the Somali port city of Eyl in the semiautonomous Puntland region, officials said.

The newspaper reported more than 300 hostages are being held and several hijacked ships are docked there.

"These pirates are well-armed groups with rocket-propelled grenades and automatic weapons," said Bile Mohamoud Qabowsade, an official in the Puntland region.

"Even superpower governments have been unable to chase away the pirates. What do you think a feeble, semiautonomous Puntland government can do?" he added.