(BBC News) Swiss voters go to the polls on Sunday to decide whether to tighten up their gun laws to conform with European Union regulations.

Switzerland is not a member of the EU, but is part of the Schengen open-border treaty.

After the 2015 Paris attacks in which 130 people died, the EU issued Schengen members with new restrictions on automatic and semi-automatic weapons.

The EU hopes the rules will help police in Schengen countries.

These states now work together and share information on a daily basis, to establish where weapons used in crimes came from.

But the proposals have raised hackles in Switzerland, which has a long, and for many Swiss, proud tradition of gun ownership.

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