California police reportedly made 12 arrests on Monday after a speech by Israel's U.S. Ambassador Michael Oren descended into chaos.
Hecklers interrupted Oren's lecture at University of California, Irvine, over 10 times, shouting "killers" and "how many Palestinians did you kill?"
Oren took a 20 minute break after the fourth protest, only to be interrupted again by young men yelling at him every few minutes, local press reported.
Many members of the audience also applauded Oren.
The arrested students were apparently members of the university's Muslim Student Union, which had publicly condemned Oren's visit earlier in the day.
In a statement printed by the Orange County Register, a newspaper, the union said:
"We condemn and oppose the presence of Michael Oren, the ambassador of Israel to the United States, on our campus today.
"We resent that the Law School and the Political Science Department on our campus have agreed to cosponsor a public figure who represents a state that continues to break international and humanitarian law and is condemned by more UN Human Rights Council resolutions than all other countries in the world combined."
Oren eventually completed his speech, some time later than scheduled, but did not take questions from the audience as planned.
University Chancellor Michael Drake was booed by some and applauded by others when he told the audience that he was embarrassed by the outburst.
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