Talor Hartshorne was on shift at the B&M store in Batley on Tuesday, February 15, when she turned round and spotted her daughter, Maisie Glynn, standing next to her.
Maisie had somehow managed to leave the grounds of Batley Parish Junior, Infant and Nursery School, on Stocks Lane, where she is a pupil in year one, during the lunch break and navigate her way to her mum's place of work - a distance of almost half a mile.
Luckily she was unhurt in the incident but Talor said it could have been much worse.
"She was in the school playing and having her lunch, then managed to leave the school grounds and head into Batley without any of the teachers realising she was missing," Talor said.
"I was at work at the supermarket and turned round and my daughter was there.
"I took her back to school to find out what was going on and they didn't know she had gone.
"It's disgusting to have allowed that to happen.
"She's only five years old. It was very lucky that I was in a place that she has visited before.
"It could have been a very different situation. It's a very busy town."
Talor says she will not be sending her daughter back to Batley Parish School and is now looking for a new school for Maisie to attend.
"I have now taken my daughter out of that school," she said. "I told them that they are not to be trusted."
Philip Sunter, head teacher at Batley Parish Junior, Infant and Nursery School, said: “The safety of all of our pupils is always our number one priority and we are thoroughly investigating how this was able to happen.
"We offer our deepest apologies to the parents of this pupil.
"I would like to reassure all parents that this is an isolated incident and something we are taking incredibly seriously.”
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