Dozens of people have been injured as thousands of supporters of the deposed president, Mohamed Morsi, hold anti-military demonstrations across Egypt, security sources say.

The violence in the city of Dakahlia erupted after Morsi’s opponents attacked the Muslim Brotherhood supporters rallying against his trial that will be held on Monday.

In another protest in Egypt's second largest city of Alexandria, security forces fired tear gas to disperse demonstrators demanding Morsi’s reinstatement. Over 100 protesters have been injured and dozens more detained there.

Similar rallies were held in the capital Cairo and other major cities across the country. The angry demonstrators called for the downfall of the army-backed government that ousted the country’s first democratically-elected president.

Morsi’s supporters have been holding weekly demonstrations to condemn the interim government’s harsh crackdown on Muslim Brotherhood and the arrest of its leaders and members.

They have been demanding justice for Brotherhood supporters killed in the army crackdown following Morsi’s ouster in early July.

The interim government took power after Morsi was ousted by the army on July 3.

Morsi has been held in an unknown location since his overthrow. He is due to stand trial on November 4 on charges of inciting violence.

Hundreds of supporters of the group have been killed in clashes with the army over the past few months.