A police car was smashed up by two yobs on a motorbike in Brinnington.
The pair of offenders threw a missile at the police vehicle on Blackberry Lane at the junction of Northumberland Road at 10pm on Wednesday.
The windscreen was smashed, injuring the two police officers inside.
Police investigating believe the incident could be connected to an attempted robbery at a nearby newsagents earlier that night.
A member of staff at the Lifestyle Express in Berwick Parade was threatened by two men armed with baseball bats at around 9.35pm.
A GMP spokesperson said: "At this stage it is unknown whether these two incidents are connected."
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Police have released photographs of the damage and appealing for anyone with information to come forward.
A statement, posted on GMP Heatons & Reddish, said: "We are appealing for any information regarding both these incidents, including dash cam footage or CCTV, and would urge anyone to come forward to assist with the Police investigations that are currently ongoing.
"Contact can made by ringing 101, Live Chat via the GMP website or alternatively Crime stoppers on 0800 555 111 quoting the log numbers above."
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