After four years, Egypt has permanently opened the Gaza Strip's main gateway to the outside world.

The move to lift most travel restrictions on Gaza residents brings long-awaited relief to the territory's Palestinian population and a significant achievement for its Hamas rulers. But it raises Israeli fears it will be easier for militants to go in and out of Gaza.

The first busload of passengers crossed into Egypt on Saturday morning at the Rafah terminal, where about 400 Gazans awaited.

Egypt and Israel have maintained a blockade over Gaza since 2007 to weaken Hamas following its violent seizure of the area. But after the ouster of Egyptian President Hosni Mubarak in February, Egypt's new military rulers decided to ease the blockade.