A police officer and two recruits were shot dead Wednesday by unidentified gunmen in Arish city in North Sinai province, a security source told Xinhua.
"The militants set an ambush for a police vehicle and opened fire at it near Gisr al-Wadi area in Arish, killing a colonel and two police recruits," the source added, noting that the perpetrators managed to run away after the attack.
Terrorist activities have escalated in Egypt since the overthrow of former Islamist president Mohamed Morsi by the military in July 2013 following mass protests against his one-year rule and the massive crackdown on his supporters that left nearly 1,000 killed while thousands of others were arrested.
Anti-government attacks have since extended from the Sinai peninsula to the capital Cairo and other provinces across the country, with Ansar Bayt al-Maqdis (ABM) group claiming responsibility for most of them.
In late October, a blast targeted a big military checkpoint in North Sinai's Sheikh Zuweid city, leaving more than 30 soldiers killed and tens of others injured.
In response, Egypt announced a three-month curfew and a state of emergency in some parts of North Sinai.
The ABM has recently announced its allegiance to the Islamic State (IS) Sunni radical group in Iraq and changed its name to "Sinai State" as one of the so-called groups under IS leader Abu Bakr al-Baghdadi.