Greenfield Police first heard of the heists in September. They continued through October and have since spread.
Flushing valves have been nabbed from MATC, Waukesha County Technical College, ITT Technical Institute, UWM and most recently Marquette.
The suspect is described as being in his 20s or early 30s, carrying a backpack, wearing jeans, a dark jacket and a dark winter hat.
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