Armed police swooped on a car in Harpurhey on Wednesday, according to eyewitnesses.
A large number of marked and unmarked police arrived at the scene on Rochdale Road shortly before midday.
The car was allegedly stopped by police at a car wash.
A witness said there were three males and a woman inside the vehicle when it was pulled over.
One man appeared to have been detained by officers.
Adbullah Sadaqat, who runs the Manchester Car Wash nearby, said a car pulled in before being 'surrounded by police cars'.
"There must have been around six or seven police cars - some of them were unmarked and the police had guns.
"They surrounded the car", he told the M.E.N .
“There were three men and a woman in the car.
"One of the men didn’t look very old, more like a teenager, and the woman looked like she worked at a hospital.
"She was wearing a nurses uniform and was crying.
“I saw police pulling what looked like a knife from the car.
“I don’t know what happened. They didn’t tell us anything. People kept asking me what was going on but it was nothing to do with us.
“I think the men were arrested and the car was taken away by a recovery truck.”
The Manchester Evening News has contacted Greater Manchester Police for a response.
