A COVERT operation into the region's drug activity by Ballarat and Bacchus Marsh police culminated in four arrests this morning.
The operation, code-named Blackwork, resulted in search warrants being executed at an Underbank Boulevard address just after 5.30am.
Members from the Ballarat CIU, Moorabool CIU and the Ballarat Divisional Response Unit were involved in the early-morning raid.
Police allegedly seized a clandestine laboratory, quantity of amphetamine, a quantity of cocaine, crystal methylamphetamine and cannabis.
It is also alleged a 0.22 caliber handgun was found at the address.
Four men at the home have been taken into custody and are assisting police with their inquiries.
Three men from Bacchus Marsh are set to be charged with manufacturing amphetamine, possessing implements to manufacture drug of dependence, possession of drug of dependence and firearms offences.
The males, aged 26, 22, and 19 years, will be brought before the Ballarat Magistrates Court later today.
A fourth man from Melton, 31, has been charged with possession of drugs of dependence and has been bailed on his own undertaking to appear Ballarat Magistrates Court on May 24.
Investigations are ongoing into the cases.