University police said they are taking the threats very seriously, but so far, they have found no evidence to back up the threats.
Extremist groups connected with animal rights organizations claimed responsibility in an effort ot get researchers to stop using live animals for medical research.
"UCLA has got to understand that this is serious business, that activists are not gonna just keep asking politely and nicely forever for them to stop torturing these animals," said Dr. Jerry Vlasak, press officer for the Animal Liberation.
Back in August, the home of a UC Santa Cruz researcher was firebombed, forcing two adults and two small children to escape from the second floor of their home. An animal rights activist claimed responsibility for that attack.
UCLA van drivers are being told to check underneath their vehicles for any suspicious vehicles or any vandalism, just in case.
In a statement, UCLA said, "The tactics used by these extremists opposed to the use of laboratory animals in research are beyond reprehensible. It is difficult to put into words our outright contempt and disgust at terrorists targeting commuters and property."
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