The incident happened at the downtown location of Tim Horton's in Langley, British Columbia, southeast of Vancouver.
The disturbing incident was captured on the shop's security camera and uploaded to a variety of social media sharing platforms Wednesday, including Liveleak and YouTube.
The woman then pulls down her trousers and defecates on the floor before scooping it up and throwing it.
At one point, the woman grabbed a couple of tissues from the counter and continued to argue with the employee at the desk. She proceeded to take the tissues, wipe her hands and her backside and throw them at the staff too. She then scoops up the excrement and tosses it over the counter.
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Luckily, a barrier behind the woman prevented other diners from witnessing her actions.
Holly Largy confirmed that officials were called regarding the incident and the woman was arrested and and released.
The woman is due to attend a court hearing at a later date, she said. "As matters escalated, the Team Member contacted local authorities for assistance", said Tim Hortons in a statement, The Province reports.