A greengrocer whose stubborn refusal to abandon imperial weights and measures led to him being dubbed a Metric Martyr has died from a suspected heart attack at the age of 39.

Steven Thoburn waged a three-year battle after being prosecuted for selling in pounds and ounces on his market stall, not metric units as required by an EU directive. The dispute, which was taken to the House of Lords, stemmed from the sale of a bunch of bananas worth 34p.

Thoburn was prosecuted by Sunderland city council for breaching the Weights and Measures Act. His imperial scales were confiscated and he was given a six-month conditional discharge in 2001.

Despite widespread public support, he failed to get the conviction overturned in the high court and the Lords.

Thoburn, who leaves a wife and three children, is understood to have collapsed and died at his home on Sunday after complaining of chest pains.

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