U.S. forces handed over to authorities in northern Somalia on Monday nine pirates they captured after capsizing their boats at sea, a local official said.

The handcuffed men, paraded before reporters in the enclave of Puntland, are expected to appear in court this week, said Mohamed Said, Puntland's deputy police commander.

"The U.S. Navy told us they captured nine pirates on Friday and they handed them over to us this afternoon as you can see," he told reporters in the port of Bosasso.

"These pirates were captured as they were trying to hijack ships in the Gulf of Aden ... the U.S. navy capsized the pirates' boats." U.S. officials were not immediately available to comment.

Somali pirates, typically in small groups aboard speedboats, have won millions of dollars in ransom from shipowners after boarding and seizing cargo vessels. The surge in piracy has caused international alarm and warships from several countries have rushed to try to curb the hijacks.

Newly elected President Sheikh Sharif Ahmed, a moderate Islamist, and his new government aim to bring peace to the chaotic Horn of Africa nation.

It has had no effective government since warlords ousted dictator Mohamed Siad Barre in 1991 then turned on each other.

Violence has killed more than 17,000 people since the start of 2007, uprooted 1 million, and caused a humanitarian crisis.