Gaza activists surrounded by Egyptian riot police in central Cairo
Several hundred people have joined demonstrations on the Israel-Gaza border to protest against the Israeli blockade of the territory.
The demonstrators, who marched to the Erez crossing point from both sides of the border, included dozens of international activists.
The Egyptian authorities have allowed about 80 protesters to cross into the Gaza Strip from Egypt.
Dozens more, however, scuffled with police in the capital Cairo.
Some report say protesters were injured by Egyptian police.
More that 1,000 international activists had gathered in Cairo in the hope of being allowed into Gaza but were refused because of what Egyptian officials called the "sensitive situation" in the Palestinian territory.
Israel maintains a strict blockade of Gaza, tightened in 2007 when Hamas took over the strip, banning virtually all exports and allowing in only humanitarian basics.
Egypt's border is open only occasionally, to people not goods.
Much of what Gazans need is supplied through illegal tunnels under the Egypt-Gaza border. Israel says this is also a supply route for weapons.