About 180 Civil War-era cannonballs found in the grounds of the US's oldest arsenal have been detonated in a New York quarry.
Army 1st Sergeant Kieran Dollard of the Fort Drum-based 725th Explosive Ordinance Disposal Unit said the cannonballs were found in the grounds of the Watervliet Arsenal, on the Hudson River just north of Albany.
The explosives were moved 64 kilometres north to a quarry in South Glens Falls, where they were detonated. The munitions had been discovered during construction projects over the years and stored in the facility's museum, which closed last autumn.