(4:55 a.m. EST) -- A British cruise ship avoided potential attack in the Indian Ocean yesterday when it was approached by a speedboat manned by what is thought to have been Somali pirates.

The 9,570-ton, 348-passenger Spirit of Adventure, a sister line of Saga Cruises, was en route from Madagascar to Zanzibar when a suspect vessel came suspiciously close during dinner, having followed the ship at a distance for some time beforehand. A spokesman for Spirit of Adventure told Cruise Critic: "As a pure precaution, passengers were moved to the lounge and full security measures were put into place."

Captain Frank Allica powered the ship up to full speed and the unidentified boat subsequently gave up the chase. Naval authorities have been informed of the event and Spirit of Adventure is safely in Zanzibar today.

Although cruise lines don't reveal their security strategies for obvious reasons, typical precautions taken for dangerous crossings like this one include briefing the passengers on what do to in the event of an attack; looping coiled razor wire around the ship's railings; blacking out windows at night and forbidding anybody from going on deck after dark. Further defences include high pressure fire hoses and acoustic sound weapons.

Spirit of Adventure, which is on a two-week cruise from Mauritius to Mombasa, is one of the few cruise lines still operating in the Indian Ocean. Others, including Seabourn and Star Clippers, pulled out because of the threat from pirates while MSC Cruises, Fred. Olsen and Hapag Lloyd all tweaked their itineraries for 2010/2011 to dodge attacks.

--by Sue Bryant, Cruise Critic Contributing Editor

Discuss this story.