A new warning over the dangers of inhaling "laughing gas" has been issued after dozens of used cannisters were found in the historic heart of Leicester.
The discarded silver cannisters were discovered in Castle View, next to the Newarke Houses Museum this week.
Most had been removed today, although one or two were still dotted around the area.
The gas, which can be bought legally in small canisters and has practical industrial uses, produces a euphoria but floods users' lungs and...
