Militants on Wednesday killed eight Egyptian policemen in an attack on a checkpoint in the restive Sinai Peninsula, the authorities said, as the country marked the Muslim Eid al-Fitr holiday.
The northeastern region has long been the hotbed of an insurgency linked to the Islamic State group and security forces have regularly been hit.
"Terrorist elements targeted a checkpoint west of El-Arish early this morning... The exchange of fire killed five terrorist elements and eight police were martyred," an interior ministry statement said.
Some militants escaped and security forces are following "their movements", the ministry added.
A security source said reinforcements had been dispatched to the checkpoint near El-Arish, capital of North Sinai province.
"The checkpoint is currently surrounded by the army and police," he said.
Three members of the Central Security Force, under the control of the interior ministry, were also wounded in the attack and taken to El-Arish public hospital, a medical source told AFP.
Egyptian state television said there were fears the death toll could rise amid reports of attacks on multiple checkpoints. It broadcast still images it said were of the slain attackers.
There was no immediate claim of responsibility for the bloodshed.
'Hard for a mother'
Egyptian social media users paid tribute online to the policemen killed as people were celebrating the end of the holy month of Ramadan.
"It's very hard for a mother waiting for her son to ring her and send her Eid greetings to receive a call that he has been killed," prominent actor Mahmoud al-Bezzawy wrote on Twitter.
The interior ministry did not release the identities of the slain officers.
Egypt has for years been battling insurgents in the North Sinai affiliated with the Islamic State group.
Hundreds of police officers and soldiers have been killed in militant attacks which surged after the army's ouster of Islamist president Mohamed Morsi in 2013 by general turned president Abdel Fattah al-Sisi.
Police raids in May killed 16 suspected militants in North Sinai.
The interior ministry said last month it had intelligence that militants were planning attacks on "important and vital facilities", as well as prominent figures in El-Arish.
In late 2017, North Sinai was the scene of the deadliest attack in Egypt's modern history when militants killed more than 300 worshippers at a mosque, without any group claiming responsibility.
Sisi has presented himself as a bulwark against terrorism and a rock of political stability in a region hit by turmoil.
In February 2018, the army launched a nationwide offensive against the Islamists focused mainly on the North Sinai.
According to official figures, around 650 militants have been killed since the start of the operation, while the army has lost some 50 soldiers.
No independent statistics are available and the region is largely cut off to journalists, making verification of casualty figures extremely difficult.
The Egyptian government has organised rare media visits closely supervised by the military.