Updated

Police have arrested 50 members of the opposition Muslim Brotherhood group for organizing Gaza protests in Cairo, a security official said Monday.

He said the arrests Monday followed calls by the outlawed Brotherhood on members and other opposition groups to stage more demonstrations to protest Israel's Gaza offensive.

The official spoke on condition of anonymity because he is not authorized to speak to the media.

Protests have taken place across Egypt since the Jewish state began its Gaza offensive Dec. 27. In some cases, police clashed with protesters and made arrests.

Egypt borders Hamas-ruled Gaza, where more than 500 Palestinians have been killed and about 2,000 wounded as a result of the Israeli offensive. Israel says the objective of the offensive is to stop Hamas from firing rockets at its southern communities.

The militant Palestinian group has ideological ties to Egypt's Muslim Brotherhood, the country's strongest opposition group.

The arrest of the Brotherhood members in Cairo, however, did not stop some 3,500 group members from taking to the streets Monday to protest the Gaza offensive in the city of Assiut some 200 miles (320 kilometers) south of Cairo,

The protesters chanted anti-Israeli slogans and blocked off the city's main roads. Large number.