HAMPDEN, Mass. (WWLP) - Police are investigating a large-scale marijuana growing operation on Thresher Road in Hampden on Tuesday. The Hampden Police Department along with Massachusetts State Police and the Drug Enforcement Administration (DEA) were outside the house on 41 Thresher with over 20 law enforcement officials dressed in hazmat suits removing plants from inside and lining them up in the front yard. Hampden Police Sgt. Michael Cooney told 22News that a marijuana grow lab was being dismantled after a several months-long investigation led by Detective Jason Roath of the Hampden Police Department. More than 1,000 marijuana plants were seized during a search warrant early Tuesday morning. Marijuana grow house busted in Brimfield VIDEO: Police activity on Thresher Road A 22News viewer sent a video of more than a dozen cars and trucks lining the narrow street. "I saw them taking it out, I couldn't believe it. How did they plant it? The shades were always down," said neighbor Fred Frangie. He said several family members, friends, and neighbors told him that they smelled weed coming from the house, but he never believed it until now. MAP: Thresher Road in Hampden No arrests have been made at this time. Local News Headlines POST Commission decertifies former Holyoke police officer Rare weather phenomenon to occur as potential Hurricane Helene makes landfall Monson woman arrested after police pursuit into Connecticut Massachusetts snowmobiler who crashed into parked Black Hawk helicopter awarded $3 million WWLP-22News, an NBC affiliate, began broadcasting in March 1953 to provide local news, network, syndicated, and local programming to western Massachusetts. Watch the 22News Digital Edition weekdays at 4 p.m. on WWLP.com.