CAIRO — Gunmen shot dead three policemen near the Suez canal city of Ismailia and seized their weapons, bringing to five the number of policemen killed in the last 24 hours in Egypt.

Attacks on security force personnel have surged since the army ousted Islamist president Mohamed Morsi in July and the military-installed authorities launched a deadly crackdown on supporters of the deposed leader.

The unknown assailants late Tuesday opened fire on a police car traveling along the highway linking Ismailia to Cairo, killing the three policemen, one of them an officer, security officials said.

The attackers then seized their weapons and fled.

Earlier on Tuesday, unknown assailants shot dead a police officer and a policeman in separate attacks in the Suez canal city of Port Said and in Ismailia.

The latest deaths bring to 22 the number of policemen killed in militant attacks since January 23, according to an AFP tally based on reports by security officials.

An al-Qaeda inspired group, Ansar Bayt al-Maqdis or Partisans of Jerusalem, has claimed most of the deadliest attacks in Egypt since Morsi’s ouster, saying they were in revenge for a deadly crackdown by the security forces on his supporters.

More than 1,400 people have been killed in the crackdown, according to Amnesty International, and thousands jailed.