TAWAS CITY, Mich. (Michigan News Source) – Four Chinese nationals, one of which is in the U.S. illegally, are facing charges in connection with a massive illegal marijuana growing operation discovered in Iosco County.

A search warrant lead Michigan State Police to a warehouse where they discovered 5,057 marijuana plants estimated to be worth a street value of more than $5 million.

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Police arrested Meiqing Chen, Wenying Wu, Changning Zhen, and Zhenhong Nei during a traffic stop. Officials said Zhenhong Nei is in the country illegally and under U.S. Immigration and Customs Enforcement (ICE) detainer. The other three face at least 15 years in prison if convicted.

Authorities believe the four suspects are part of a larger operation spanning the globe.