AN Egyptian police brigadier-general has been killed in bombings outside Cairo University.

There was no immediate claim of responsibility for the attack but Islamist militants have carried out similar operations in a fast-growing insurgency that is threatening the country's security.

Two bombs planted among trees outside the university also wounded five from the security forces who had been guarding the facility.

Bombings and shootings targeting the security forces have become commonplace in Egypt since the army deposed Islamist President Mohamed Mursi last July following mass protests against his rule.

The government this week put the death toll from such attacks at nearly 500 people, most of them soldiers and police.

Analysts expect militants to increase violence ahead of the May 26-27 presidential election.

Abdel Fattah al-Sisi, the general who toppled Mursi, is expected to easily win the vote. The military leader enjoys backing from supporters who see him as Egypt's saviour.