Anglian Water engineers are trying to get to the bottom of what is causing a stink at a Peterborough shopping centre.
Shoppers visiting Serpentine Green in Hampton have complained of a smell of sewage while picking up goods at the centre.
The centre is home to a number of shops, restaraunts and cafes, and now Anglian Water have been called in to try and deal with the issue.
A large upgrade of the centre was finished last year.
The smell issue was raised by Roy Proud, who said: "When is something going to be done about the stench at the Serpentine Green ( #SepticTankGreen ) Shopping Centre? Coming in the other day via the North entrance by the new @marksandspencer Food Hall the smell was appalling."
On Twitter, a spokesman for Serpentine Green said: "Centre management have confirmed we are working with drainage companies and Anglian Water to identify the problem to resolve this. We hope that this will be resolved soon."
A spokesman for Tesco, the largest store in the centre, apologised and said: "Good Morning Roy, I'm so sorry about this. I'm so sorry about this. I can totally understand how unenjoyable this would make your shopping experience.
"I have spoke with the Tesco Duty Manager and he has confirmed that this is an ongoing issue which the Shopping Centre owners are aware of