(Reuters) - Israeli naval forces intercepted a cargo ship in the Mediterranean on Sunday then boarded the vessel to search for suspected weapons, military officials and media reports said.

Israel routinely patrols the seas for ships suspected of carrying weapons destined for Palestinian militants. A year ago Israel seized a cargo ship it said held Iranian-supplied arms intended for the Hamas-ruled Gaza Strip.

Israeli military officials, said the ship, the HMS Beethoven and flying a Liberian flag, was seized about 160 miles off the Israeli coast, and one source said troops were conducting a "very thorough search of its cargo."

The ship would be released if nothing "suspicious" is found on board, a military official said.

The officials suggested there had been no confrontation aboard the vessel, that the captain had consented to the search and that so far "nothing outstanding has been found".

One of the officials described the interception as "routine protection of our territorial waters".

Israeli media reports said the military suspected the ship may be transporting weapons intended for Palestinian militants in the Hamas Islamist-ruled Gaza Strip.

In the earlier seaborne interception in March 2011, Israel said the vessel it seized had set sail from Syria, had stopped in Turkey and had been destined for Alexandria in Egypt.

Palestinians use a network of tunnels to smuggle weapons into Gaza from Egypt. Gaza militants often fire rockets at Israel and say it is in response to Israeli raids in their coastal territory.(© Thomson Reuters 2012. 04/22/12)