Cairo: Three Egyptian policemen were killed and four other people, including a police officer, wounded Friday in an attack in the Suez Canal city of Ismailia, security and medical sources said.

Two cars approached a checkpoint in a residential neighbourhood of the city and two armed assailants opened fire at the policemen, the security source said.

The policemen responded, killing one of the assailants while the other fled.

The source said the attack was likely a "terrorist act", describing it as the first of its kind in nearly three years in mainland Egypt, which has largely been spared the deadly insurgency in the Sinai peninsula.

In the past few years, attacks against security forces have been concentrated in the restive Sinai, where jihadists affiliated with the Islamic State group continue to operate.

In May, 11 soldiers were killed in an attack in western Sinai.