Three South Korean tourists and the Egyptian driver were killed while at least 13 tourists were wounded by the explosion, Health ministry spokesman Ahmed Kamel told AFP news agency.

The bus was carrying 32 South Korean tourists and had arrived at Taba from the ancient Greek Orthodox St Catherine's monastery in central Sinai.

The bomb went off during a drop-off at a Hilton hotel.

The cause of the explosion was not immediately clear, but officials believe it was either a car bomb or a roadside bomb, reported AP.

According to an Israeli police spokesman the bus was on its way to the occupied territories of Palestine.

Taba is a Red Sea resort area commonly visited by foreign tourists. The area has been the scene of attacks before, most notably in 2004 when the Taba Hilton hotel was bombed, leaving 34 people dead - mostly Egyptians and Israelis.

Sinai has been rocked by several attacks since the removal of Egyptian president Mohammed Morsi by the army last July.

SHI/SHI