Egypt's interior ministry told police in the Sinai Peninsula to raise a state of emergency after obtaining intelligence that "jihadists" might attack their forces there, state media reported.
Officials have expressed growing worries about security in the desert region which borders Israel and is home to a number of tourist resorts.
"The minister of interior has raised the level of emergency in north and south Sinai after receiving information that jihadist groups intend to attack police buildings there," General Osama Ismail, an interior ministry official, was quoted by MENA news agency as saying on Saturday.
Last August, attackes killed at least 15 Egyptian policemen in an assault on a police station at the border between Egypt and Israel, before seizing two military vehicles and attempting to storm the border.
It was the deadliest incident in Egypt's tense Sinai border region in decades.
Israel has accused Palestinian fighters in Gaza of involvement in armed activity in Sinai, where insecurity has grown since Hosni Mubarak was toppled in Egypt's 2011 revolution.
President Mohamed Mosri has pledged to get a grip on security in Egypt but struggled to assert control over an entrenched security establishment.
Last week, thousands of riot police and conscripts across the country went on strike over a variety of grievances.