Police in Egypt have killed dozens of militants on Saturday during security raids on their hideouts, the interior ministry has said.
The raids killed "40 terrorists" in Giza and North Sinai on Saturday morning, according to a statement from the ministry.
It said the militants were planning a series of attacks on tourist sites, churches and military personnel.
The raids followed Friday's roadside bomb attack on a tour bus in Giza, according to BBC.
No group has yet said it was behind the blast, which killed three Vietnamese tourists and an Egyptian tour guide, but Islamist militants have targeted tourists in Egypt in the past.
Police killed 30 militants during two early morning raids in Giza, while the remaining 10 were killed in El-Arish, the capital of North Sinai province, the interior ministry said.
"A group of terrorists were planning to carry out a series of aggressive attacks targeting state institutions, particularly economic ones, as well as tourism... and Christian places of worship," the ministry statement said.
It added that police had seized bomb-making materials, ammunition and a large number of weapons during the raids.
Security is already tight in Egypt, with the tourist season at its height and the country's main Christian minority, the Copts, preparing to celebrate Orthodox Christmas on January 7.
The roadside bomb went off at about 18:15 (16:45 GMT) on Maryoutiya Street in Giza's Haram district as the bus carrying 14 Vietnamese tourists was passing, according to official accounts.
Four people were killed and eleven others were injured in the incident, which is the first affecting foreign tourists in Egypt in more than a year.
Prime Minister Mostafa Madbouly has said the bus deviated from its planned route without alerting security forces, although the driver has denied this.