CAIRO (AP) ― An Egyptian court sentenced to death on Monday 529 people accused of an attack on a police station that left one policeman dead, in a mass trial that lasted only two sessions and raised an outcry from rights activists.

The verdicts against the men, said to be supporters of ousted President Mohammed Morsi, are subject to appeal and would likely be overturned, rights lawyers said.

But they said the swiftness and harshness of the rulings on such a large scale deepened concerns that Egypt’s courts have been deeply politicized and that due process is being swept away amid the crackdown on Morsi’s Muslim Brotherhood that followed his July overthrow.

Amnesty International said it was the largest single batch of simultaneous death sentences they had seen in recent years anywhere in the world.

In response, the Egyptian Foreign Ministry said in a statement that the country’s judiciary is “entirely independent and is not influenced in any way by the executive branch of government.”

Egyptian authorities are holding a series of mass trials of alleged Morsi supporters, with anywhere from dozens to hundreds of defendants at a time. Monday’s verdicts by a court in the city of Minya, south of Cairo, were the first such mass trial to issue death sentences.

The court held two sessions. In the first on Saturday, the judge angrily shouted down requests by defense lawyers for more time to review the prosecution’s case for the hundreds of defendants. In Monday’s session, security forces barred defense lawyers from entering the courtroom on orders from the judge, the provincial police chief said.

“We didn’t have the chance to say a word or to look at more than 3,000 pages of investigation to see what evidence they are talking about,” Khaled el-Koumi, a lawyer representing 10 of the defendants, told The Associated Press.

All but around 150 of the defendants in the case were tried in absentia. The judges acquitted 16 defendants.

A senior official involved in courtroom security said that 154 defendants were brought in to the court on Monday. He said that the minute the judge announced the verdict, defendants in the cage screamed “You butcher” to the judge. The official spoke on condition of anonymity because he was not authorized to speak to the press.

The 545 defendants in the case were charged with murder, attempted murder, joining an outlaw group aiming at toppling the regime and stealing government weapons in connection with an attack on a police station in August in the town of Matay in Minya province. One police officer was killed in the attack. The violence was part of rioting around the country, sparked when security forces stormed two pro-Morsi sit-ins in Cairo, killing over 600 people, on Aug. 14.

After the verdict was announced, families of the defendants protested outside the court building in Minya, shouting “Down with military rule.” Police arrested three people from the protest. Fears of a backlash by Morsi supporters prompted security officials to go on alert around Minya province.

Mohammed Zarie, a Cairo-based human rights lawyer who was not involved in the case, said the verdicts show that Egypt’s judiciary is turning “from a tool for achieving justice to an instrument for taking revenge.”

The judge appears to have made his decision to issue a swift verdict after tumult at the start of the session from defense lawyers and the more than 100 accused held in the cage, according to descriptions of the session by lawyers and court officials.