An anonymous tip-off to police has led to the discovery of a cache of guns buried under a concrete slab. Semi-automatic rifles and a revolver were found hidden on a vacant residential property that had recently been sold in Huntly, near Bendigo in central Victoria. They were unearthed using a jackhammer last week. Police say the weapons had been there for 20 years and all 10 were in an excellent condition. Each gun was secured with poly pipe and wrapped in garbage bags containing motor oil. It's believed the tip-off came as part of the national firearms amnesty, which guarantees anyone who hands in weapons will not be prosecuted. The firearms will be destroyed in coming weeks. Australian Associated Press