STAMFORD - Stamford police say a man is in custody and six illegal guns are off the streets after an undercover gun bust last night. Investigators say the operation took place on East Main Street and led to the arrest of Mike Lotz, a convicted felon. They say he was allegedly selling the weapons around parts of the city, and was captured with the help of the Alcohol, Tobacco, Firearms and Explosives team from Darien. Authorities say Lotz is likely to be arraigned tomorrow, and that a juvenile is facing charges for serving as his alleged lookout.