An Egyptian security official says troops have arrested nine Islamic militants in northern Sinai believed to be behind a deadly attack last weekend that killed 16 Egyptian soldiers.

The official told the Associated Press that early Friday the troops stormed a house in Sheik Zweid, close to Rafah border crossing with Gaza Strip, and caught the nine while they were asleep. Among them was Selmi Zeyoud, whom the official described as a "dangerous element" and a brother to a slain jihadist.

The official spoke on condition of anonymity because he was not authorized to speak to the press.

The arrests are the first since Sunday's surprise attack in which gunmen stormed an army checkpoint by the borders with Gaza and Israel, killed 16 soldiers, then drove into Israel.

Egypt reopens border

A Hamas official says Egypt has temporarily reopened its border with Gaza but only to allow the passage of Palestinians back to the coastal territory.

Egypt closed the crossing in the wake of Sunday's deadly attack in the Sinai Peninsula.

Maher Abu Sabha said Friday the crossing would remain open for two days to allow Palestinians in Egypt to return to Gaza. Egyptian border guards are still prohibiting Gazans from entering Egypt.

Gaza's Hamas rulers lobbied Egypt last month to open the border and end a longtime blockade. But after Sunday's deadly ambush, Egypt closed the crossing, accusing Gaza militants of helping co-ordinate the assault.

The closing was a blow to Hamas' hopes of establishing better ties with Egypt.