A child and three other people were injured when a car driver hit pedestrians in two separate locations, police have said.
Three people, including the child, suffered minor injuries in Woodgate Avenue, while a woman was airlifted to hospital with potentially life-threatening injuries following a crash in Whitworth Road.
A 49-year-old man was arrested on suspicion of assault and attempted murder. He has been detained in hospital.
Greater Manchester Police said the crashes in Rochdale at about 14:30 BST were “not being treated as terrorism related”.
Assistant Chief Constable John Webster said: “We are deeply saddened by the tragic events that occurred in Rochdale today. Our officers are supporting the victims and their families at this time.
“We believe this to be an isolated incident with one lone offender arrested and in hospital.”
He urged anyone with information to contact police.
