Feb. 12 (Bloomberg) -- U.S. naval forces captured seven suspected pirates in the Gulf of Aden after responding to a distress call from a chemical and oil products tanker.

The operation took place after the 420-foot (128-meter) vessel Polaris, sailing under a Marshall Islands flag, sent a call to all nearby ships at about 3 p.m. local time yesterday, the U.S. 5th Fleet said in a statement. The Polaris crew said seven pirates in a skiff tried to force their way aboard using a ladder. Crewmembers removed the ladder and stopped the hijacking.

Sailors from the U.S. guided missile cruiser Vella Gulf found and intercepted the skiff, which was carrying “several weapons,” the fleet said. The suspects were being held on the Vella Gulf until they can be transferred to a temporary holding facility on a Navy supply ship, a 5th Fleet spokeswoman, Lieutenant Stephanie Murdock, said today in a phone interview.

The Vella Gulf is part of a multinational task force that conducts counter-piracy operations in the Gulf of Aden, Arabian Sea, Indian Ocean and the Red Sea. The incident yesterday was the first time the U.S. contingent in the force has captured suspected pirates, according to the statement. U.S. sailors and Marines in the region previously were restricted to operations to “disrupt and deter” pirates.

About 20 warships now patrol the Gulf of Aden, an unavoidable transit point for the 50 ships a day that use the Suez Canal. The increased naval presence has cut piracy in the region, according to the U.S. Navy.

Last year, pirates attacked 165 ships and seized 43 off the coast of Somalia, up from 58 attacks and 12 seizures in 2007, the French military said.

To contact the reporter on this story: Caroline Alexander in London at calexander1@bloomberg.net.

Last Updated: February 12, 2009 04:52 EST