The University of California at Irvine has suspended the campus's Muslim Student Union for one year and placed the group on disciplinary probation after members of the group repeatedly interrupted a campus speech in February by Israel's ambassador to the United States, according to a letter released on Monday.

The hecklers shouted down the ambassador, Michael Oren, at times calling him a "killer" and scuttling parts of the speech. Video of the event drew international attention and sparked a debate about the tactics of the protesters, who said they were angry about Israel's treatment of Palestinians.

A university review found that the group had planned the disruption in advance, and that it had violated a number of campus policies, including disruption of university activities and disorderly conduct. The group will be banned from the campus until at least September 2011, and its members will be required to complete 50 hours of community service, according to the letter, supplied by the university in response to a public-records request.