At least 18 police forces, including a general, have been killed in Egypt's Sinai Peninsula after militants ambushed their convoy, in one of the deadliest terrorist attacks in the restive region since January.

According to the country’s security and military officials, militants on Monday first detonated a number of roadside bombs that destroyed and set ablaze four armored vehicles and another one, which was carrying equipment used for signal jamming purposes.

The assailants, whose identities were not yet known, later opened fire at survivors and commandeered a police pickup truck.

There was no immediate claim of responsibility for the attack, but authorities said that they bore the hallmarks of the Velayat Sinai, a local affiliate of the Daesh Takfiri terrorist group, formerly known as Ansar Beit al-Maqdis, which pledged allegiance to Daesh in 2014, and usually carries out similar assaults against the government forces.

The incident occurred some 30 kilometers west of Arish in northern Sinai, the heart of long-running militancy now led by the Velayat Sinai terror outfit.

According to the state news agency MENA, security forces entered a gun battle with militants in the vicinity of the blast site and managed to slay several of them.

The deadly assault came just a day after security forces carried out two simultaneous raids on apartments in a crowded district in capital Cairo. The apartments were allegedly occupied by members of a militant cell planning terror attacks in the capital.

At least 10 suspected militants were killed in the raids. Police said the militants had sneaked into Cairo from the volatile northern Sinai.

At least 26 Egyptian soldiers were killed or wounded on July 7, 2017, in attacks on checkpoints in the Sinai Peninsula.

In March, militants claimed the lives of 10 troopers during an army raid in Sinai's central region. Four months later, at least 26 Egyptian soldiers were killed or wounded in attacks on checkpoints in the restive peninsula.

Since its emergence in 2013, Velayat Sinai has killed hundreds of members of Egyptian security forces. The terror group later expanded its assaults to target members of Egypt’s Coptic Christian community as well as foreigners visiting the country.

Egypt has been suffering from a spike in terrorist attacks targeting civilians in the mainland over the past year. That has prompted the government to impose a state of emergency and widen a controversial crackdown, which critics say has mostly targeted dissidents.