Protests against Egyptian President Mohammed Morsi's decree giving himself sweeping new powers claimed their first life, media reports said.
A 15-year-old identified as a Muslim Brotherhood member was killed and 60 people injured in an attack late Sunday in the Nile Delta city of Damanhour on an office of the movement, which supports Morsi, DPA reported.
The death came ahead of a meeting Morsi is to have Monday with the country's top judges to try to defuse the crisis over Thursday's decree, which has sparked protests that have injured more than 500 people across Egypt.
Morsi, who headed the Muslim Brotherhood's Freedom and Justice Party before becoming Egypt's first elected president, decreed that all his decisions and laws since taking office in June are immune to legal challenge, an order that the opposition condemned as undermining democracy.
Morsi supporters took to the streets by the thousands Sunday night in a number of cities, and police and Morsi critics clashed in Cairo and Al-Baheira province.
At least 5,000 people protested against Morsi's decree in Cairo's Tahrir Square alone.
Morsi's office said Sunday that the constitutional declaration is temporary until the new constitution is approved.