Semi-automatic rifles, a machine gun and a crossbow are among a cache of more than 200 illegal weapons seized from a home near Adelaide, with some found in hidden rooms.
Investigators from the Serious Firearms Branch discovered the arsenal at the rural property late on Friday and arrested a 53-year-old on firearms charges.
The haul included handguns, semi-automatic rifles, about 200 kilograms of ammunition, a crossbow, silencer, gunpowder, reloading equipment, throwing knives, daggers, bayonets and a quantity of military ammunition.
Officers also seized more than 30 registered firearms during a search that lasted three days.
Superintendent Stephen Howard said it was disturbing that so many dangerous and illegal weapons were being kept in the community.
"Some of these weapons are the most lethal that are made," he said.
"Not only were they insecure but there were magazines loaded in the vicinity."
Supt Howard said one of the weapons seized was "made for war".
"It's purely designed for killing people. This one has a folded bayonet used for hand-to-hand combat. It has no other reason but for killing people," he said.
"The same could be said for the machine gun."
The man charged over the weapons haul was refused police bail and was expected to appear in Adelaide Magistrates Court on Monday.
Police said he could face further charges.