NAIROBI, Kenya-- A Kenyan lawyer says a court has freed 17 Somali men accused of piracy who were captured by the U.S. Navy last year.

Jared Magolo, who represents the 17, said Friday that a magistrate's court in the Kenyan coastal town of Mombasa ruled that there was insufficient evidence to prove that the Somali men attacked MV Amira, an Egyptian-flagged ship, in May 2009.

Magolo says the magistrate blamed the loss of the case on the U.S. Navy for not providing video and photographic proof that they claimed to have.

Somali pirates usually seize ships in the Gulf of Aden, one of the world's busiest waterways. They earn multimillion dollar ransoms with little risk because Somalia has not had an effective government for 19 years.