At least 15 Egyptian policemen were killed and seven wounded in an armed attack on a police station in North Sinai on the border between Egypt and Israel in what the Israeli government said was an attempt to storm its border.
Egyptian state television reported that an Islamist militant group was behind the attack.
A spokeswoman for the Israeli army said a "group of terrorists" had attacked the border post killing about 15 people. The Israeli air force had targeted one vehicle that tried to infiltrate Israel, while a second vehicle had exploded at the border crossing, she said.
Egyptian security sources said the attackers had used a stolen police vehicle to launch the attack and fired live ammunition at police officers at the station.
A television journalist based in North Sinai said the area was sealed off by security forces, blocking the road from the main town of al-Arish in the direction of the Gaza border crossing at Rafah.
Earlier on Sunday, an Israeli air strike killed a Palestinian gunman from a radical Islamist group and wounded another as they rode a motorbike in southern Gaza near the Egyptian border.
It was not immediately possible to confirm whether the two incidents were linked.
Israel has previously accused Palestinian militants in Gaza of involvement in militant activity in Sinai, where insecurity has spread since the U.S.-aligned Egyptian president, Hosni Mubarak was toppled by a citizen revolt last year.
Gaza is governed by Hamas, a Palestinian Islamist movement which, while also hostile to the Jewish state, is considered too moderate by many Salafis and has at times clashed with them during law and order drives.
