Swiss apartment explosion injures four

Four people were injured, one of them seriously, when an explosion ripped through an apartment in northwestern Switzerland on Tuesday, regional police said.

Georges-Andre Lozouet, spokesman for the Neuchatel police, said the explosion took place around noon in an apartment in a residential building. He said the seriously injured person was taken to hospital by helicopter.

Swiss public broadcaster RTS published video showing flames and thick black smoke coming from the windows of a first-floor apartment, with significant damage to the lower part of the building's facade.

Lozouet said the cause of the explosion remained unclear. He said the fire that followed had been extinguished, but the area remained cordoned off in the mid-afternoon.