Dozens of people in Cairo, the Egyptian capital, have been arrested after clashes erupted between security forces and protesters outside the Muslim Brotherhood's headquarters.

Police on Sunday fired tear gas at the protesters who were demonstrating against an alleged assault on journalists who claimed they were attacked by Brotherhood members on Saturday evening during coverage of a meeting,

"We came to defend Egypt, Egypt which is resembled in journalists and political activists, who went down today not for any political interests," Mossad el-Masry, a spokesman for the 6th April Youth Movement, an activist group, said.

"Today we send a message to the National Salvation Front: you are sitting in your chairs while people are dying on the street.

"A message to all those sitting on their seats: our girls and our brothers and sisters are being beaten and tortured."

The journalists said that after a group of activists sprayed anti-Brotherhood graffiti on the ground outside the group's Cairo headquarters, the Brotherhood guards attacked them with sticks and chains.

A Muslim Brotherhood spokesman said in a statement that guards outside the building were provoked and insulted by the activists and journalists.

Egypt is currently mired in another wave of unrest that has plagued the country since the ousting of Hosni Mubarak in a pro-democracy uprising two years ago.