A German cargo ship carrying 11 crew members in the Gulf of Aden called for help as it was being attacked by Somali pirates, but by the time a helicopter arrived to render assistance the pirates were already in control, officials said Wednesday.

It was the latest seizure by high-seas bandits who are holding hundreds of merchant mariners hostage.

The German-owned ship, the MV Victoria, was captured Tuesday afternoon 75 miles south of Yemen, said Lt. Nate Christensen, a spokesman for the Bahrain-based U.S. 5th Fleet. He had no information on the condition of the 11 Romanian crew members aboard the Antigua- and Barbuda-flagged ship.

German Defense Ministry spokesman Thomas Raabe said the Victoria had been sailing in an unaccompanied convoy, but was a relatively easy target because of its slow speed and low railing. A Turkish frigate responded to a call for help by sending a helicopter, but the ship already was in the pirates' hands by the time it arrived, he told reporters in Berlin. The frigate was between 80 and 100 nautical miles from the ship at the time, Raabe said.

The Gulf of Aden is one of the world's most important shipping lanes, connecting Europe and Asia via the Red Sea and the Indian Ocean. It is used by 20,000 ships a year and has become the world's hot spot for pirate attacks.

At least 19 ships are now being held by Somali pirates, and about 250 sailors from countries around the world being held hostage in the Gulf of Aden and directly off Somalia's eastern coast.

The pirates' wealth is all the more shocking considering Somalia's poverty. There has been no effective central government in nearly 20 years, plunging the arid country into chaos. Nearly every public institution has crumbled.

Last year, dozens of ships were seized and an estimated $1 million per boat was paid in ransom for their release, according to analysts. Each pirate is believed to get on average $10,000 for a successful hijacking.

Ship owners typically airdrop the plastic-wrapped cash into the sea.

An international flotilla of warships has been patrolling the Gulf of Aden and nearby waters, and has halted many attacks, but experts say the area is simply too vast to stop all pirate attacks.

Antigua and Barbuda's government said the vessel is registered with the European Union anti-piracy flotilla operating in the region and was in the recommended East-West corridor of the Gulf at the time of the hijacking.

The government statement said eight pirates hijacked the ship, and they were believed to be steering it toward the Somali coast town of Eyl — a known hotbed of piracy. The statement said the ship has a crew of 10, and the discrepancy could not immediately be explained.

The Romanian representative of the International Transporters' Federation, Adrian Mihalcioiu, said the incident happened in the strip secured by vessels operating under a NATO mandate. He said the ship was laden with rice and was traveling between India and Saudi Arabia.

In Haren, Germany, shipping company Intersee said it manages the hijacked ship. Manager Mark Schoening declined to discuss details of the hijacking.