The violence continued Tuesday on the campus of Tehran University, where security forces were using tear gas and arresting students, according to reports and video clips relayed through Twitter and Internet postings. There were protests at large squares near the university as well, witnesses said. Iran’s official IRNA news agency reported that the clashes began after groups of pro-government students carrying pictures of Iran’s supreme leader, Ayatollah Ali Khamenei, clashed with protesters on campus.
During Monday’s demonstrations, there were fewer people with clothing or banners in the trademark bright-green color of Mr. Moussavi’s presidential campaign. And there were more chants aimed directly at Ayatollah Khamenei — a taboo that has increasingly eroded since the election. In addition to the now-common chants of “death to the dictator,” some protesters chanted “Khamenei knows his time is up” on Monday.