The white male was spotted wandering the aisles of an Asda store in Cambridge wearing a black SS uniform.
Paul Dutton, from Cambridge, claimed responsibility for the stunt using his Twitter account.
Under the name Operation Fail Safe, he said: ‘I wear a black SS armband in Asda twice a week for past three years.
‘I’ve shopped in Asda since the place was opened twice a week, this is how Asda repay me for my loyalty.’
He said he had wanted to hand out cards promoting his website, which explains the reasons for his fascination with Adolf Hitler.
A shocked customer snapped the man entering the store, with a cap and red armband, yesterday at around 2pm.
He was asked to leave after a number of shoppers at the Beehive Centre store complained to management.
‘We had a number of customer complaints so we asked him to leave the store,’ said a spokesman for Asda.
Police were called but a spokesman added: ‘By the time we got there he had already left peacefully’.
Rosina Rusin, 60, from Milton, said many customers were left upset by the incident
‘I was waiting in a queue when a lady came up and she was really quite distressed about it,’ she told the Cambridge News.
‘People’s mouths were falling open. You are not going to come out like that unless you want to draw attention to yourself.’
Neil Doron, 40, from Cambridge, added: ‘He was just standing there in all that gear. It’s not very nice. At first I thought it was just a guy in costume.
‘I do not think people should have that on at any time of year because of what it stands for. It’s not nice for people in Cambridge.’