Police backed by armoured vehicles have stormed the campuses of at least two prominent Egyptian universities to quell anti-government protests by students, security officials say.

Protests took place on Sunday at Cairo University and al-Azhar University. They were organised by supporters of ousted Islamist President Mohammed Morsi.

Student protest spokesman Youssef Salhen said the protesters clashed briefly with police outside the al-Azhar University.

A security official told the Associated Press that at least six people were arrested at al-Azhar, where police fired tear gas.

Activists say at least 65 students have been arrested over the past two days.

Authorities have intensified security at universities nationwide to prevent the resurgence of student protests. Last year, at least 16 students were killed during anti-government protests.

Morsi's supporters continue to hold small, scattered protests despite a crackdown after he was ousted in July 2013.

Interior Ministry spokesperson Hani Abdel-Latif said his ministry had drawn up a security plan to deal with student protesters.

"Security forces, and in coordination with the administration of these universities, have been stationed outside the walls of universities to deal with student outlaws," he said.

Source: Al Jazeera and agencies