Dunblane massacre

The Dunblane massacre took place at Dunblane Primary School in Dunblane, Stirlingshire, Scotland, on 13 March 1996. 
Thomas Hamilton killed 16 children and a teacher before committing suicide. It is the deadliest mass shooting in British history.
Later, and influenced by this event, two new Firearms Acts were passed. They greatly restricted private ownership of firearms in Great Britain.
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