"There is a large amount of rat feces in the library, in the work room, the cafeteria," the anonymous employee told our partners at KGTV.
That employee didn't want to be named over fears of retribution, but he told our partners at KGTV he's noticed the problem for months and has even seen a rat in the courtyard of the school.
The school is Mira Mesa High School, which as of 2011 had more than 2,500 students.
KGTV is vowing to stay on top of the story -- and put in a call to the school's principal. A district spokeswoman says the school will look into it, but there are no details yet as to a possible resolution.
According to the Centers for Disease Control and Prevention, rats and other rodents can transmit a host of diseases, including hemorrhagic fever, rat-bite fever and salmonellosis.
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