Daniel Webster Elementary School Principal Mauro Cruz said the latest incident was the seventh break-in since February 2004, WDIV-TV, Detroit, reported Thursday.
"They raided the refrigerator in one of the classrooms," he said.
Two computers, a printer and two TV sets also have disappeared in the past five days, WDIV said.
Officials said they don't know how to make the building more secure without creating the illusion that it's a "jail for the kids."
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