CAIRO (AP) — The leader of Egypt’s Muslim Brotherhood denied his group was to blame for violence as he appeared in court Monday for the first time since being detained following the ouster of the Islamist president last summer.

The trial against Mohammed Badie and other senior Islamists comes as authorities tighten a crackdown on dissent, arresting dozens of protesters in a raid on Al-Azhar University, Sunni Islam’s most prominent educational institution.

In a sign of increasing intolerance for demonstrations and the widening of a crackdown, prosecutors have also sent two dozen secular activists, including one of Egypt’s most prominent bloggers, to trial on charges of violating a new law that restricts protests.

The military-backed government argues the crackdown on protests is necessary to restore stability, particularly ahead of a referendum expected next month over amendments to an Islamist-drafted constitution.

The vote is considered a milestone in the political transition plan adopted following the popularly backed July coup that ousted Islamist President Mohammed Morsi. The military-backed government has promised the charter would set Egypt on the path to democracy and is to be followed by parliamentary and presidential elections.

Meanwhile, authorities have cracked down on Morsi supporters, widening a net of arrests and legal prosecution to include senior leaders as well as students and protesters.

The authorities are seeking through the prosecutions to show that the Brotherhood fueled violence during Morsi’s one-year presidency and after the coup — and to give legal justification for imprisoning its leaders.

Amid tight security Monday, Badie and 14 other senior leaders of the group appeared in the defendants’ cage for the opening of a trial focusing on July protests in which at least five people were killed, including a former army officer.

Addressing the courtroom, Badie denied the Brotherhood was behind any violence.

“Me and my group are not offenders or defendants. We are victims in the face of those that killed thousands of citizens and peaceful protesters,” he said according to Egypt’s state news agency.

Badie said dozens of his group’s offices were torched during the protests against Morsi. “My son was killed, my home was torched and shot at, and despite all that there is not a single investigation into this,” he also told the court.

The hearing was held inside the prison complex where Badie has been held, in a police academy transformed into a courtroom. Officials had cited security concerns for failing to transport him to a previous, separate trial, also over accusations of inciting violence at earlier protests.

The defendants interrupted Monday’s proceedings repeatedly, denouncing the charges against them as brought by authorities they don’t recognize. El-Beltagy asked the panel of judges to recluse themselves because “they are sitting in the wrong place” and trying the wrong people, he said.

Arriving in the courtroom, Badie first prayed for those “who lost their lives for Egypt’s sake.” His son was among those killed during security crackdowns on pro-Morsi protests in August that left hundreds killed. The judge adjourned the trial to Feb. 11.

Morsi himself is on trial for inciting murder. His trial opened last month and is to resume in January.

Brotherhood defense lawyer Mohammed el-Damati said the trials are politically-motivated.

“I think all these trials are political but masqueraded as criminal cases,” he told reporters following the trial.

Meanwhile, protests by pro-Morsi supporters continued, turning violent Monday when students at Al-Azhar University students set three police vehicles on fire, prompting police to chase them through the campus.

Dozens were arrested and one student was seriously injured in the clashes, according to health ministry official Khaled el-Khateeb.

It was the second consecutive day of protests by students at the university, where regular demonstrations against the military’s ouster of Morsi have been held since the start of the academic year in September.

Sunday’s protests were fuelled by the referral to trial of 21 students on charges of rioting and storming the office of the Grand Imam of Al-Azhar Mosque weeks ago. Just last month, 12 students from the same university were sentenced to 17 years for participating in protests and clashes on the campus.

In a statement Monday, a Brotherhood-led group hailed student protests at Al-Azhar and elsewhere, calling them the “pulse of the revolution and its mainstay toward deliverance. It called for protests to support them on Tuesday.

The political arm of the Brotherhood, the Freedom and Justice Party, accused authorities of waging a “war of annihilation” against Al-Azhar students.

Youssef Salehein, a student leader in Al-Azhar University, said the police had blocked gates of the universities with armored vehicles and were arresting students from classrooms. He said he saw at least three students injured by shotgun pellets.

The Interior Ministry, responsible for the police, said about 200 pro-Morsi students had blocked the streets outside Al-Azhar university campus — a major thoroughfare in eastern Cairo, and pelted police with rocks and firebombs, damaging at least three police vehicles and injuring policemen.

Protesters retreated to the campus after police fired tear gas and kept up their rioting there, damaging staff cars and other university properties, the ministry said in its statement.

Police spokesman Hani Abdel-Latif told Egyptian private CBC TV that 58 students were arrested. Abdel-Latif accused the Brotherhood of seeking to destabilize the country, and to derail the political road map.

“They want to create a crisis,” Abdel-Latif said of the Brotherhood. “They are trying to provoke the police and residents to create violence.”

Copyright 2013 The Associated Press.