Police are investigating after a hydroponic drug setup was found at a house in Port Macquarie at the weekend.

About 4am (Saturday 19 March 2016), a three-year-old boy was found by a member of the public walking along Gordon Street wearing only a nappy. Officers from the Mid North Coast Local Area Command were contacted and attended.

As part of their inquiries, officers attended a Hollingworth Street residence. While at the residence, police allege cannabis plants were located, along with equipment used in their cultivation.

A crime scene was established as further investigations were conducted. A search warrant was executed and 17 cannabis plants, more than 300g of cannabis, an unregistered firearm and a prohibited weapon were seized.

About 4.45pm, a 39-year-old woman attended Port Macquarie Police Station and was charged with two offences including, take part in enhanced indoor cultivation of prohibited plants in presence of children, and take action that results in health/physical damage to a child.

She was granted conditional bail to appear at Port Macquarie Local Court on Wednesday 6 April 2016.

Other agencies have been notified.