Officers were called at around 11.30am on Wednesday 18 November to reports that a man at the restaurant was threatening an employee with a knife off Whitefield Road, Bredbury.
A member of the public was able to engage with the man – with support from response officers – and encouraged him to give up the knife while officers were able to move the woman to safety.
A 24-year-old man was arrested and taken to custody, and has since been detained under section 136 of the Mental Health Act.
Enquiries are ongoing and anyone with information is urged to contact police.
Detective Sergeant Matt Tarr, of GMP’s Stockport CID, said: “This was a terribly frightening ordeal for the victim of this incident and officers are working with her employer to ensure that she – and other staff members affected – are receiving the support they need at this time.
“I would like to thank the member of the public who bravely tried to intervene and put his own safety at risk to try and diffuse the incident – this action ensured that when police responded just moments later we were able to prevent anyone being hurt and a man was arrested.
“Our enquiries are very much ongoing and we encourage anyone with any information about the incident to contact police as to aid our enquiries. We understand the drive-thru was quite busy at the time and we hope anyone who saw what happened can share whatever information they have with us.”
Anyone with information should call police on 0161 856 9821 quoting incident number 926 of 18/11/2020. Details can be passed anonymously to the independent charity Crimestoppers on 0800 555 111.