Staff at a sweet shop are "sick and tired" after finding human poo by their back door for the seventh time.
They say they dread opening in the morning for fear of finding more excrement left by the unknown offenders.
And although Northampton Borough Council dealt with the mess the first three times, they have now been told they would have to pay hundreds in waste management fees for this to continue.
Frustrated staff have now had to clean the incidents up themselves four times in the past month.
Trudi Daurie, director of The Sweet Bee sweet shop, in Alexandra Terrace, Harborough Road, Kingsthorpe, said: "We've had two incidents this week.
"We have to check the back door first thing in the morning in case they've struck again.
"We've put up signs reminding people that our back door is not a toilet but it hasn't stopped them.
"I don't know if it's someone coming back drunk from a night out or if it's a homeless person but we're just so sick of it."
The Sweet Bee is a charity that offers young adults aged between 19 and 25 with special educational needs work placements in their sweet shop.
They work closely with the Northgate Arts College and Beehive for special needs students aged 16 and up.
Trudi said: "The only way for our students who use a wheelchair to enter the shop is through the back door, and we have to lead them past that. How do you explain that? It's traumatising."
The first three incidents happened in September 2016, which were cleaned up by Northampton Borough Council.
But since the offending messes started again February, The Sweet Bee staff have had to clean it up themselves four times.
Trudi said: "We've been keeping logs. When we speak to the council now, they say nothing can be done for 10 days. We've just resigned to cleaning it ourselves now as it's on our private property.
"It just makes me so sad. We shouldn't have to deal with this."
Shez Webb, executive headteacher of Northgate Arts College and Beehive, said: "Whoever is doing this needs training like everyone else.
"We're trying to teach young people about proper hygiene in the work place and then this happens. And then we have to explain how an adult did that."
The shop is now considering installing CCTV or a security light to help catch or ward off the offenders.