KOTA KINABALU, Malaysia -- Search efforts continue on Tuesday for the missing in the boat accident off Malaysia's Sabah state on North Borneo.

Ahmad Puzi Ab Kahar, director general of Malaysian Maritime Enforcement Agency, said the operations would cover 3000 square nautical miles with planes and ships of his agency as well as Malaysian navy and air force.

Neighboring Brunei also sent two aircrafts to join the efforts, he said, adding that aircrafts have entered the search area at six in the morning.

Twenty Chinese tourists and two crew members have been rescued so far, after their boat sank off Sabah on Saturday. Malaysian authorities said five people remained missing, including 4 tourists and a crewman.