Black Sabbath fans were allegedly seen urinating on the 7/7 memorial in Hyde Park, following the band's show as part of British Summertime, London.
A photo (see above) has been shared online, reportedly taken after the second of this year's huge Hyde Park shows. Police are now investigating the incident - which took place just two days before the anniversary of the London bombing (5 July 2014).
"Police are aware of an image which shows a purported public order offence being committed at the 7/7 memorial," said a spokesperson for The Metropolitan Police.
"Officers are making immediate enquiries. Police take matters of this nature seriously."
The image was initially shared on Reddit, with users suggesting that the individuals seen in the image were most likely unaware of the memorial's significance.