In the morning hours on Monday 27 July 2007, IOF put two lit up buoys in the North Gaza sea. According to the field investigations, the signs are composed of a heavy metal block that was thrown into the sea and linked with an iron pillar ends with light. The first signs was put in one kilometer away from the coast of Beit Lahyia, in the sea and three kilometer away from the separation line. The second sign was put two kilometers away from the first sign. The two signs form a line demarcating a no-go zone for Palestinian fishermen, although the IOF have not commented on them.