Another member of Egypt's security forces has died from injuries sustained in a bus blast on Monday morning in the village of Beheira, health ministry spokesperson Hossam Abdel-Ghaffar told Ahram Online, raising death toll to three.

Two members of Egypt's security forces have been killed earlier  and at least 27 others injured in a bombing that targeted their bus in Beheira, north of Cairo, Ahram Arabic news website reported.

The early Monday blast struck a passing bus that was carrying the policemen to work posts in a village in the northern governorate, some 160 km north of the capital.

It was not immediately clear if any civilians are among those wounded.

Egypt has been battling a growing Islamist insurgency since the 2013 ouster of Islamist president Mohamed Morsi.

The attacks, based in the northern Sinai Peninsula, have mostly targeted security forces, but also extended to the mainland.

The violence has been spearheaded by Ansar Beit Al-Maqdis, which pledged allegiance to the Islamic State group last year.

On Thursday, a massive car bomb exploded near a national security building in a densely populated residential neighbourhood, wounding 29 but leaving no casualties.

The bombing was claimed by the group previously known as Ansar Beit Al-Maqdis