JERUSALEM - Police blocked an Israeli protest boat today from trying to break through Israel's naval blockade and carry activists and aid supplies to the Gaza Strip.

The boat was set to depart from the small port of Jaffa, near Tel Aviv -- the latest in a series of similar attempts to attract attention to Israel's sanctions against Gaza by sailing there.

The journey was organized by Israeli Arab political parties and not-for-profit groups.

Israeli Arab lawmakers and other activists were to have been among the roughly 100 passengers and the cargo was to include basic food supplies, medicine, toys and sweets for an upcoming Muslim festival.

Police officers contacted the boat's owner and warned him that sailing to Gaza would be a violation of Israeli law, which forbids Israeli citizens from entering Gaza.

Israel and Egypt imposed a blockade on Gaza after the militant Hamas group seized power in June 2007.