A top US university has canceled its plans for a graduation speech by a Muslim student over what it says are safety concerns, after pro-Israel groups criticised her selection.The decision by the University of Southern California is the latest controversy to roil American higher education since the conflict between Israel and Hamas erupted in October.Asna Tabassum, who has been attacked online for "antisemitic and anti-Zionist rhetoric," had been selected as class valedictorian.USC's valedictorian is chosen by college officials from among scores of applicants with high academic grades.They represent the graduating class and deliver a speech at graduation in front of up to 65,000 people.But on Monday the university's provost, Andrew Guzman, announced the May 10 ceremony would go ahead without the speech."Unfortunately, over the past several days, discussion relating to the selection of our valedictorian has taken on an alarming tenor," Guzman said in a statement."The intensity of feelings, fueled by both social media and the ongoing conflict in the Middle East, has grown to include many voices outside of USC and has escalated to the point of creating substantial risks relating to security."Guzman's statement gave no specifics, but the Los Angeles Times quoted Erroll Southers, the university's associate senior vice president for safety and risk assurance, as saying the institution had received threats by email, phone and letter.Individuals "say they will come to the campus," he said.Tabassum criticised the decision, which she said was the result of the university "succumbing to a campaign of hate meant to silence my voice.""Although this should have been a time of celebration for my family, friends, professors and classmates, anti-Muslim and anti-Palestinian voices have subjected me to a campaign of racist hatred because of my uncompromising belief in human rights for all," she said in a statement.The fallout from the Israel-Hamas conflict has been felt around the world, and is particularly intense on US college campuses, where both pro-Israel and pro-Palestinian groups say they are being victimised and silenced.On Wednesday the president of the prestigious Columbia University in New York will become the latest campus leader to face questions from US lawmakers about whether her institution is doing enough to combat anti-Semitism in the student body.