Disturbances have broken out in the Heywood area of Rochdale, police have confirmed.
Gangs of youths have congregated and it is believed Asian takeaway businesses have been targeted, sources said.
A spokesman for Greater Manchester Police said: "We became aware of congregations of men gathering in Heywood this evening. We are getting some reports of disturbances.
"There has been no reports of serious injuries. The owner of one takeaway restaurant has had his car attacked."