Security officers were stationed outside the Alexandria Criminal Court after police and demonstrators clashed, al-Masry al-Youm reported.
Calm was restored, police said
Judges had been forced to adjourn the trial after fights erupted between defense lawyers and plaintiffs.
Ten protesters were arrested.
Civil Defense forces extinguished several fires at the building that had been started by protesters, authorities said.
Court documents could be seen strewn around the streets.
Egypt's upheaval in 2011 led to the ouster of President Hosni Mubarak.