A humanitarian ship carrying 12 international activists, including Swedish climate advocate Greta Thunberg, is sailing off Egypt’s northern coast in a renewed effort to break Israel’s longstanding

Thunberg, a climate campaigner, is among 12 activists aboard the Madleen, which aims to break the blockade of Gaza and deliver humanitarian aid.

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.