The militants opened fire on the group - a mix of police and armed forces - during a raid on their hideout near the Bahariya oasis, south-west of Cairo, the Interior Ministry said.
The small extremist group Hasm claimed the attack, saying in a statement that 28 members of the security forces were killed, with 32 injured.
"A number of policemen" were killed in the shootout, the interior ministry said, but it did not provide an exact number.
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He was shirtless at the end of the bed. "After this happened, I didn't want to go out, and I didn't want to go to my castings. And when I looked at him, he said, 'You have really nice t**s. "I followed him, and we went into the bedroom, and it's dark".
Terrorist attacks, mainly targeting police and military, increased after the ouster of former president Mohamed Morsi in 2013 by military following massive protests against his rule.
Hundreds of soldiers and police have been killed in the violence.
Islamist militants have launched several major attacks, most recently targeting churches in Cairo and other cities with the loss of dozens of lives. Hasm has taken credit for the murders of judges and police officers in the country over the past year, Al Arabiya reports. Firefights with the Hasm militant group south of Cairo continued into darkness.
But unlike their parent organisation in Iraq and Syria, they have been unable to seize population centres in the peninsula bordering Israel and Gaza.