Five Islamist militants were killed in an explosion south of the Egyptian city of Rafah near the border with Israel and Palestinian-ruled Gaza on Friday, the state news agency MENA said.
The Egyptian military said there had been two explosions but gave no further details. Soldiers were searching the area in the North Sinai region to find out more, army spokesman Ahmed Ali said in a statement.
MENA, quoting witnesses, said at least five "Jihadists" were killed near Rafah in an explosion on Friday evening.
The witnesses said the explosion was the result of the destruction of a launchpad ready to fire rockets into Israel.
An Israeli army spokeswoman in Jerusalem declined to comment on the incident.
Militants based mainly in North Sinai near Israel's border have escalated attacks on Egyptian security forces and other targets since July 3, when the army deposed Islamist President Mohamed Mursi and installed a new government.
The Egyptian army said on Wednesday it had killed 60 militants in the Sinai Peninsula in the month since then.