One Israeli soldier and three militants were killed during a skirmish at the border with Egypt, the Israeli military said.
Three militants armed with weapons and explosive belts tried to cross into Israel and were targeted by troops, a military statement said.
One soldier was killed in the exchange of fire and another was wounded.
The Israeli military killed all three militants, the statement said.
A senior Egyptian security official, however, said that one of the militants died after detonating his explosive belt. The Israeli forces killed the other two, said the Egyptian official, who declined to be named because he is not authorized to speak with the media.
None of the attackers were able to slip into Israel, the military said.
"According to initial findings, the IDF force successfully prevented a large-scale attack on Israeli civilians," the military said in its statement.
Egyptian officials believe the militants were known jihadists and members of the same Bedouin tribe, the Egyptian official said. They were wanted by Sinai police, the official said.