Swedish cops who rushed last Saturday to a block of flats in Stockholm after concerned residents alerted emergency services of a possible gas leak, found that the tremendous whiff was actually down to fermented herring.

Officers backed by two fire trucks and an "emergency gas leak team" swooped on the Södermalm building's stairwell, polluted by noxious fumes eminating from a traditional surströmmingsskiva (fermented herring party) in one of the flats.

Firefighter Björn Hörnsten told Swedish radio: "The person who called the police had spoken to several neighbours in the house who also thought it smelled like gas, and were worried.”

He added: “They’ve got gas in the building, so I find it a bit strange that they called us. They ought to know what it smells like when you turn on a gas stove. It doesn’t smell like surströmming at all."

The Local describes the stench of surströmming as "something less dangerous" than explosive gas. Anyone who's ever got within sniffing distance of an open can of the Swedish delicacy might beg to differ.

Experts are divided as to whether surströmming or Icelandic hákarl is the world's most repulsive nosh. Our informant Mike Richards describes the latter's decidedly non-piquant shark odour as resembling "a well fermented urinal on a hot summer's day".

Indeed, it's the only food we're aware of that's capable of temporarily disabling sweary food botherer and turkey specialist Gordon Ramsay, as this clip from his show The F Word demonstrates (language NSFW):

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