Three people are being treated for serious injuries following reports of a stabbing in Denton, police said.
Greater Manchester Police were called to the incident at Yew Tree Road on Saturday morning.
Emergency services attended the scene, and a woman was taken to hospital for further treatment.
Her injuries are not thought to be life threatening.
Officers say a further two people believed to be involved have attended hospital with serious injuries, but they are not thought to be life threatening.
Police are describing it to be an isolated incident with no wider risk to the public, but extra officers are being deployed to the area for community reassurance.
Detective Sergeant Pete Goddard of GMP Tameside district said: “A scene will continue to be in place whilst we conduct further searches and enquiries.
"If you have any questions or concerns, please speak to one of our officers, they are here to help.“
"GMP are taking a robust approach to knife crime in the Greater Manchester area, and this is no exception."
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