Egypt has launched a "comprehensive" security operation against "terrorists and criminal elements" across the country, a military spokesman said.
Colonel Tamer Rifai announced on Friday the implementation of a plan to push out armed groups in the Sinai Peninsula, parts of the Nile Delta and the Western Desert.
"Law enforcement forces began this morning implementing the plan of comprehensive confrontation against the terrorist and criminal elements and organisations in the north and central Sinai and other areas in the Delta of Egypt and the desert back in the west of the Nile Valley," Rifai said in an urgent televised statement.
"This comes in addition to training and other operations on all strategic directions in order to tighten control of the ports of the Egyptian state," he added.
The army has already ordered hospitals to be placed on high alert, preparing extra beds and personnel, to deal with emergencies and medical evacuations.
Local media are also reporting an "unusual increase" in the number of military vehicles in north Sinai.
Egypt has for years been battling an armed anti-government campaign in the rugged and thinly populated Sinai Peninsula, which has gained pace since the military overthrew democratically elected President Mohamed Morsi of the Muslim Brotherhood in mid-2013.
Over the years, most attacks have targeted soldiers and police, but civilians have also been killed. Hundreds of people have died in the conflict so far.
In 2014, following a suicide bombing that killed 33 soldiers, current President Abdel Fattah el-Sisi declared a state of emergency in the peninsula, describing it as a "nesting ground for terrorism and terrorists".
In November 2017, at least 235 people were killed in a bomb and gun attack on a mosque in Bir al-Abed, a town in North Sinai province.
In his statement on Friday, the army spokesman called on citizens to "immediately report any elements that threaten the security and stability of the country".
Meanwhile, Egypt will go to the polls next month in a presidential election in which Sisi looks poised to extend his term in office.
Source: National News Agency