The activists had set out to protest Israel’s ongoing military campaign in the Gaza Strip, which is among the deadliest and most destructive since World War II, and its restrictions on the entry of aid.

Israel says it intercepted the 'selfie yacht' peacefully, offering snacks and water; activists claim abduction while tossing phones into the sea

There are a number of things that could cause the ship to turn around, like lack of food and water or problems with the engine.