Waterloo Regional Police have seized a handgun, suspected heroin and cocaine, as well as a cocaine press from a storage unit in Kitchener.
The search warrant was executed Thursday at a unit on Ottawa Street South.
Police have said more charges are expected.
Three Cambridge residents were arrested on Wednesday after police seized weapons and drugs.
They executed two search warrants that day, one at a residence on Glenmorris Street and the second on Livingstone Crescent.
Police seized two loaded handguns, ammunition, stun guns, bear spray and variety of other weapons.
Officers also found quantities of suspected fentanyl, carfentanil, methamphetamine and cocaine.
Two men and a woman were arrested.
No names have been released.