MELBOURNE, Fla. -

The Drug Enforcement Agency is investigating a bath salt manufacturing facility in Melbourne on Wednesday afternoon, according to agents.

Tim Reed was next door when authorities stormed the warehouse. He said he knew people were making the synthetic drug for over a year now due to the smell.

"They all came in like gangbusters they had automatic rifles, pump shotguns, weapons drawn when they went to that door down there," Reed said.

Deputies took at least four men from the scene. Agents are removing boxes of already-manufactured K2 and a bath salt product called "Cloud 9" are at Dusa Drive and Wickham Road, according to the DEA.

Possessing, selling, and making bath salts is illegal in the U.S.

No other information, including how much was recovered, has been released.

Watch Local 6 News for more details.