An unsuspecting couple in Austria were left stunned after receiving 25,000 ecstasy tablets through the post – that were intended for an address in Glasgow.

The pair, aged 58 and 59, from Linz in the northern part of the country, were left astonished after opening the parcels when they were eating breakfast.

At first, they believed the boxes contained two long-awaited dresses ordered over the internet from the Netherlands – but instead found one of the cases contained€500,000 of ecstasy, or MDMA, tablets.

A later investigation found the package was intended for a Scottish address.

A translated statement from the Upper Austria Police said: “The originally planned cosy breakfast was quickly over and the horror was great, as it turned out that in the second package was about 24,800 Ecstasy tablets worth about 500,000 euros.”

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A picture released by the force shows the cardboard box, filled with three bags that are packed with pink tablets.

The woman initially believed the colourful pills were decorative stones, but on closer inspection, her husband realised they were probably drugs and immediately returned them to the local post office.

The police added: “There too, the astonishment about the content of the package was great, which is why the City Police Command in Linz was informed.

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“In the following investigation it turned out that it was a mail misconduct - the package should have been actually sent from the Netherlands to Scotland.”

An NCA spokesperson said: "This is a live investigation and enquiries are ongoing."