Security forces on Friday fired teargas to disperse dozens of Islamists who protested in several areas in Cairo's neighbouring governorate of Giza, the Ahram Arabic news website has reported.

Protesters blocked off streets in the neighbourhoods of Haram, Badrashein and Faysal, but were quickly scattered by police.

The once-strong street movement of Islamists that followed the 2013 ouster of president Mohamed Mursi has significantly waned over the past year.

Friday's marches came three days after a court sentenced Mursi to 20 years in prison over charges of ordering the detention and torture of demonstrators involved in clashes in 2012 when he was still Egypt's elected president. It was the first verdict against the ex-president.

Authorities have designated Mursi's Muslim Brotherhood group a terrorist organisation, but the group says that it is committed to peaceful activism.