(PORT HURON TOWNSHIP) -- A combined effort between the St. Clair County Drug Task Force and the Port Huron Police-St. Clair County Sheriff Major Crimes Unit has resulted in the confiscation of a large amount of marijuana. Search warrants were served at four separate locations Friday. The first took place in the 5500 block of State Road in Fort Gratiot Township. Officers seized 72 marijuana plants and 50 pounds of processed marijuana. The plants were being grown in a greenhouse. Another raid took place at a factory in the 500 block of Memphis Ridge Road in Riley Township where 71 marijuana plants were seized. The search of a home in the 3000 block of Elk Street in Port Huron resulted in the seizure of dozens of marijuana plants and a large floor safe. Several pounds of processed marijuana was found during a raid in the 2600 block of 18th Avenue in Port Huron. Authorities say that based on the size of the plants and the quality of the marijuana seized, the street value is estimated at $2.5 to $3 million dollars. Authorities were able to confiscate 3 vehicles, trailers, 3 ATV's, a snowmobile, a motorcycle, a 33' boat and other property during the raids. A 28-year old woman and 35-year old man, both from Fort Gratiot, face charges in the case and more arrests are possible as the investigation continues.