CAIRO (Reuters) - Militants killed three policemen and injured five others in a shooting in Cairo late on Monday, the interior ministry said on Tuesday.

Attacks on security forces are common in Egypt’s northern Sinai, where the country is battling an Islamist insurgency, but targeted assaults in Cairo are by comparison rare and the shooting comes amid a campaign by militants to spread violence to the country’s mainland.

The militants drove by and shot at police stationed at an intersection of the ring road, a busy Cairo expressway, in the city’s eastern neighborhood of Nasr City, the ministry said in a statement.

Hasm, a group that the government has tied to the Muslim Brotherhood, claimed responsibility for the attack in a statement posted on its official website. The Brotherhood, outlawed by the government in 2013, maintains that it is a peaceful organization.

Little is publicly known about Hasm, though it has claimed a handful of attacks over the past year including an attempt on the life of the former Grand Mufti Ali Gomaa.

The shooting comes just weeks after two Islamic State suicide bombers killed at least 45 in deadly church bombings in Alexandria and Tanta, one of the bloodiest attacks the country has experienced in years.