At least 22 policemen were injured in Egypt in attacks on two police stations in the governorates of Alexandria and Beheira, north of the capital Cairo, state-run news agency MENA reported Saturday.

In Alexandria, 12 policemen were injured as 200 people attempted to break into Al-Raml police station after an overnight fight between some Islamist supporters and liberal opponents of President Mohamed Morsi, MENA quoted General Amin Ezz Eddin, assistant interior minister and head of Alexandria police department, as saying.

The police used minimum force to stop the assailants and arrested 13 of them after they had injured policemen and caused damage to some station facilities, Eddin said.

Meanwhile, another 10 policemen were injured at Beheira's Wady al-Natron police station as about 150 people hurled stones at the station and attempted to break into it until security men shot in the air and fired teargas bombs to disperse them.

Investigations said the riots followed a fight between two big families that injured seven people whose angry relatives attempted to break into the station demanding the police to arrest their rivals.

Violence prevailed in Egypt over the past two years since the ouster of ex-President Hosni Mubarak in 2011 due to constant political conflicts.