WASHINGTON - U.S. Secretary of State Hillary Clinton called on Wednesday for a coordinated international effort to fight piracy off the Horn of Africa and said she would send an envoy to a Somali donors conference to pursue new anti-piracy steps.

Clinton said the growing threat posed by attacks off the coast of Somalia required new strategies to prosecute and imprison pirates, track and freeze their monetary assets and secure the release of ships still held in the region.

We have to act swiftly and decisively to combat this threat, Clinton told reporters at the State Department.

These pirates are criminals, they are armed gangs on the sea, and those plotting attacks must be stopped and those carrying them out must be brought to justice, she said.

Audacious and heavily armed pirates from lawless Somalia have increasingly struck merchant ships in the Gulf of Aden, capturing dozens of vessels and hundreds of hostages and making off with millions of dollars in ransoms.

There has been no let-up in the attacks since U.S. Navy snipers killed three Somali pirates on Sunday and freed an American ship captain who had been held hostage for five days.

On Wednesday, the French navy detained 11 Somali pirates who tried to seize a Liberian-flagged merchant ship, and other pirates released a Greek-owned vessel captured in March,

Clinton said better coordination was needed to fight the problem. She will send an envoy to an April 23 meeting of Somali donors in Brussels to work on new initiatives.

21ST CENTURY ASSETS

We may be dealing with a 17th-century crime, but we need to bring 21st century assets to bear, Clinton told reporters at the State Department.

Our envoy will work with other partners to help the Somalis assist us in cracking down on pirate bases and in decreasing incentives for young Somali men to engage in piracy, she said.

She said the United States also would step up efforts to track and freeze the monetary assets of the pirates, just as it does with drug traffickers and terrorist groups.

We have noticed that the pirates are buying more and more sophisticated equipment, they're buying faster and more capable vessels, she said.

They are clearly using their ransom money for their benefit, both personally and on behalf of their piracy, and we think we can begin to try to track and prevent that from happening.

At the Pentagon, spokesman Bryan Whitman told reporters it would be difficult to bring a quick end to the attacks and the naval presence in the region could only do so much.

You can't be everywhere, he said. You could also, probably, have 600 ships out there and still not be everywhere.

Somalia Hillary Clinton