Hundreds of students have walked out of the commencement ceremony at Harvard University in protest against Israel's offensive in Gaza and the university's response to pro-Palestinian demonstrations.
US media say some of the students were apparently angered by Harvard's decision earlier this week not to allow 13 student protesters to graduate.
Students viewed this as a breach of an agreement reached with administrators last week to clear the protest encampment on campus grounds.
At the ceremony on Thursday, some students vocally urged the university to let the 13 attend.
Students have also walked out of commencement ceremonies at other universities, including Yale and Duke.
According to NHK's tally, at least 67 institutions have seen student protesters arrested or detained since April 18, when Columbia University in New York called in police to clear an encampment of pro-Palestinian demonstrators.