At least three police officers have been injured after a landmine blew up under their vehicle in northern Sinai, Egyptian security officials said.
Nearly 70 people died in July's Sharm al-Sheikh bombings
The police officers were taking part in a major security operation to search for militants suspected of involvement in several recent attacks.
However, it was not immediately clear whether the mine was planted recently or in past Israeli-Arab wars.
Officials said there had been clashes with militants in northern Sinai.
One report said 26 people had been arrested.
Police are hunting for suspects wanted over a series of deadly attacks, including a triple bombing in the Red Sea resort of Sharm al-Sheikh last month that killed almost 70 people.