Austria's presidential election, which is to be repeated next month due to irregularities in the first round, is facing another challenge to its credibility in the form of unsticking envelopes.
"This has never happened before," a spokesman for the Interior Ministry said, confirming on Thursday several cases in which the glue strips designed to seal postal votes have come unstuck, rendering the ballots invalid.
The ministry described the issue as "a new phenomenon."
Austria's Constitutional Court ruled in July that the country must repeat its presidential election because ballots and voting results were handled improperly, handing a second chance to far-right candidate Norbert Hofer who lost out on the top job by a slim margin.
Hofer and Green contender Alexander Van der Bellen go head-to-head again in the new run-off, scheduled for October 2.