A German mayor was left embarrassed after a screenshot of his computer he used to make a political point revealed his penchant for 'punishment' pornography.

Mayor Thomas Köppl posted a picture of the German Constitution to back up points he was making in a debate about the Alternative for Germany party (AfD), which is anti-Euro and immigration.

He wrote: 'The AfD isn't a party just like the others any longer. After pushing [party founder Bernd] Lucke and his democratic friends, this party no longer stands on the foundation of our Constitution.'

Mayor Thomas Köppl posted a picture of the German Constitution to back up points he was making in a debate about the Alternative for Germany party (AfD), which is anti-Euro and immigration

But the screenshot it also revealed other tabs for pages entitled 'Punishment Porn Videos', 'BDSM porno videos', and 'German slut punished'

But the screenshot also revealed other tabs on his browser, pages entitled 'Punishment Porn Videos', 'BDSM porno videos', and 'German slut punished', Bild reported on Friday.

People commenting on the story were quick to point out the BDSM pornography pages, which also included one saying 'HAMSTERS Gratis porn'.

One reader on the newspaper website wrote: 'DON'T MISS: Group guinea pig sex 'too loud' say neighbours.'

Köppl, mayor of Quickborn, near Hamburg, initially claimed that someone else had taken the screenshot, and deleted it, but eventually admitted that it was in fact him.

'Yes, I visited the sites concerned,' Köppl wrote in response to a user who shared the article from Bild.

'The mostly friendly comments distracted from the main article, that's why I deleted the screenshot.'

'Typical Bild, one part truth, one part supposition, and something wrong,' Köppl wrote in response to article in Bild.

BDSM pornography often involves women being dominated, humiliated and physically hurt.

When I got to my room I wanted to get clued-up Thomas Köppl

Köppl claims he first heard about it when overhearing a conversation on a ski-lift in South Tyrol, where he is currently on holiday, and was simply researching it.

'I wasn't so up-to-date about that, which annoys me. They were mentioning the site 'Xhamster', and when I got to my room I wanted to get clued-up.'

He claims his internet connection was too slow to watch any of the videos and he ended up reading a Wikipedia page on Fifty Shade Of Grey, the racy EL James novel, to find out about BDSM.

But he claims the fetish is not for him, adding: 'I'm sure people who like it can have a lot of fun with BDSM. I find it rather disturbing. I have a problem with violence in general.'

Some readers made jokes, and others were skeptical about his excuses.

'Are you going to change the signs in the town to Quickporn?' one person asked.