Police in Lucerne said the shooting occurred shortly after 9am local time yesterday at Kronospan, a wood-processing company in the small town of Menznau.
The local Neue Luzerner Zeitung newspaper said the shooter opened fire in the company canteen. Swiss news website 20min.ch said police confirmed three deaths – including the gunman – and said seven people were injured, some seriously.
Kronospan has around 450 employees. It was not clear who the shooter was or what his motive might have been.
Gun ownership is widespread in Switzerland, thanks to liberal regulation – a 2012 referendum to tighten controls failed – and a long-standing tradition for men to keep their military rifles after completing compulsory military service. An estimated 2.3 million firearms are owned by the country’s eight million people.
But gun crime is relatively rare, with just 24 gun killings in 2009, which works out to a rate of about 0.3 per 100,000 inhabitants.