A drive-by shooting killed four Egyptian police near a famed historical site on the outskirts of Cairo on Saturday and a military helicopter crashed due to a "sudden technical failure" northeast of the capital, officials said.
Masked gunmen on a motorcycle opened fire on a security checkpoint near Saqqara, said police Maj. Gen. Khaled Shalaby. The tourist site is home to the 4,600-year-old Step Pyramid.
No one immediately claimed the attack.
The helicopter was on a reconnaissance mission northeast of Cairo in the Ismailia province, the military said in a statement. It said crew members were injured, without specifying the number hurt or the severity.
Egypt has been battling a growing insurgency in the northern Sinai Peninsula led by a local Islamic State affiliate, which has mainly targeted soldiers and police there, but has also claimed attacks elsewhere in Egypt.
The militant group claimed responsibility for the crash of a Russian passenger plane in Sinai last month, saying it smuggled a bomb on board the airliner. Russia said the plane was downed by a bomb and suspended flights to Egypt.
Egypt has not commented on the cause of the crash, saying an investigation is still underway.
President Abdel-Fattah el-Sissi meanwhile inaugurated the construction of another side channel for the Suez Canal, the latest step in a multi-year effort to expand the crucial waterway and promote investment.
The militant attacks spiked after el-Sissi led the 2013 military overthrow of President Mohammed Morsi and launched a sweeping crackdown on his Islamist supporters.
The government has struggled to combat the Sinai-based insurgency while trying to jump-start the economy after years of unrest.