The alleged militants were killed in 3 simultaneous raids after authorities received information on future attacks against state institutions and churches.
Egyptian security forces killed 40 suspected militants in three separate incidents in North Sinai and Giza, the ministry of interior said Saturday, a day after a deadly bombing on a tourist bus in Giza killed four people.
The ministry did not say whether the suspected militants were connected to Friday's attack, but said its forces killed 30 people during raids on their hideouts in Giza where it said "terrorist elements" were planning a series of attacks.
“Information was received by national security that a group of terrorists was planning to carry out a series of aggressive attacks targeting state institutions, particularly economic ones, as well as tourism, armed forces, police and Christian places of worship,” the statement said.
Security forces also killed 10 suspected militants in North Sinai, where the country is fighting an insurgency led by the Islamic State group. State news agency MENA said that the suspects were killed in a gun battle.
No details about the suspects' identity or whether there had been any casualties or injuries among security forces have been released yet. The statement said the three raids took place simultaneously.
Three Vietnamese tourists and an Egyptian guide were killed Friday and at least 10 others injured when a roadside bomb blast hit their tour bus less than 4 km (2.5 miles) from Egypt's world-famous Giza pyramids. No group has claimed responsibility for the attack.
However, militants have targetted tourists before affecting the tourism industry, on which Egypt’s economy relies.
After militants bombed a Russian passenger jet in 2015, killing 224 people, the number of visitors to Egypt fell sharply, reaching only 5.3 million visits, down from its 14 million-peak in 2010.
An Egyptian faction of the so-called Islamic State group, Wilayat Sinai, claimed responsibility for the 2015 attack.
Egypt is battling a persistent insurgency in the North Sinai, which surged after the army overthrew democratically-elected president Mohamed Morsi in 2013. Since the coup, army commander Abdulfatah al Sisi has ruled Egypt.