An Egyptian security official says gunmen have shot and killed a policeman who was on patrol north of Cairo.

The official says the incident happened early on Monday in the Nile Delta province of Gharbiya.

He says two policemen had approached a suspicious-looking car by the roadside, when gunmen inside it opened fire, killing one policeman and seriously wounding the other.

The official spoke on condition of anonymity because he was not authorized to talk to the media.

Attacks and bombings targeting Egyptian security forces, the military, as well as government buildings and other installations have been on the rise since the military overthrew the country's Islamist President Mohammed Morsi in July 2013.