Three more men are in custody as police continue a four-month investigation into a drug-trafficking syndicate.
They were arrested on Tuesday morning after police raided properties in Victoria and New South Wales.
Detectives seized four firearms, a stolen vehicle and drugs, including cocaine and ice.
Operation Skyknight is targeting drug-trafficking in Melbourne's northwestern suburbs and regional Victoria.
Two men in their 20s from Roxburgh Park were charged with drug-trafficking and a 68-year-old from Gladstone Park was charged with cultivating and trafficking a commercial quantity of cannabis, as well as obtaining financial advantage by deception.
Police allege the 68-year-old used his position as a rental property manager to help operate several crop houses in the northwestern suburbs.
Two other men were also arrested on July 13 as part of the investigation.