Egyptians walk by a giant poster of President Hosni Mubarak that says: "We support you, we pledge our allegiance to you"
Egyptian police have arrested 25 more members of the outlawed Muslim Brotherhood, including one of the opposition group's top leaders.

The Brotherhood's secretary-general, Mahmoud Ezzat, was among those arrested in pre-dawn sweeps Sunday ahead of Wednesday's national referendum on presidential election rules. The Muslim Brotherhood and other groups have urged a boycott of the vote.

If approved, the referendum will amend the constitution so Egypt can hold its first multi-candidate presidential election in September. The Brotherhood opposes the amendment because it sets tough conditions for independent candidates, effectively excluding anyone not endorsed by the ruling party.

Egypt has arrested more than 700 members of the Brotherhood in recent weeks. The group says today's arrests are an attempt to silence influential opposition voices.

Some information for this report provided by AP, AFP and Reuters.