Clashes broke out late on Tuesday in a nearby area of Cairo where families of some of the more than 840 people killed in the uprising that led to Hosni Mubarak’s overthrow in February had gathered to honour those killed.
At least 41 policemen and two civilians were hurt, the state news agency said. The Interior Ministry said police had arrested seven people, part of a group it said was seeking to disrupt the event and stir up a riot.
It was the first such violence in weeks in Tahrir Square, the centre of the revolt that led to Mubarak being toppled. Police in riot gear and with shields blocked protesters from marching towards the ministry.
Ambulance workers treated people mostly for inhaling tear gas. A Reuters correspondent saw several people with minor wounds, including some with cuts on their heads.
“The people are angry that the court cases against top officials keep getting delayed,” Ahmed Abdel Hamid, 26, a bakery employee, said at the scene. He clutched stones in his hands.
He said police clashed with some of those gathered at the event to honour the “martyrs”, as those killed in the uprising are called. This prompted protesters to move to Tahrir.