A reported altercation happened near Gleadless Valley Pharmacy on Blackstock Road, Gleadless Valley, at about 12.35pm.
Those involved had dispersed in cars before police arrived at the scene.
Police believe one man has sustained injuries, but the extent of those injuries are unknown.
A nearby bus stop had been cordoned off by police.
Officers ask anyone with information about the incident to call 101, quoting incident number 434 of October 13.