The arrests come after Port Stephens-Hunter police began an investigation last month into the alleged manufacture and supply of methylamphetamine in the Maitland area.

Police executed a crime scene warrant at a home on Hunter Street, Maitland, at 2.30pm on Tuesday.

They found a clandestine laboratory at the rear of the property, including equipment and chemicals consistent with the supply and manufacture of prohibited drugs.

Officers from the State Crime Command's Drug and Firearm Squad Chemical Operations Unit attended to dismantle the lab and continued on Wednesday.

Other items seized include liquid believed to be a precursor for the manufacture of prohibited drugs, an electronic stun device, two pistols, a rifle scope and a set of nunchucks.

Two men - aged 47 and 39 - were arrested at the home and taken to Maitland Police Station.

Both men were charged with possess precursor intend to use in manufacture/production, supply large commercial quantity prohibited drug and possess unauthorised pistol.

They faced Maitland Local Court on Wednesday, where they were formally bail refused to reappear at the same court on January 21.