Police release image after man 'performed lewd act' on Melbourne bus

Police are calling for public help after a man allegedly "performed a lewd act" at a teenage girl on a late-morning bus ride in Melbourne's east.

Witnesses said he got on the 753 at Glen Waverley train station on April 21 and "engaged in sexual activity" directed at the 17-year-old about 11.05am.

He was believed to have left the bus, which was heading to Bayswater, near the corner of Jells and Ferntree Gully roads in Wheelers Hill.

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Overnight, police released an image of a man they think might be able to help them with their inquiries.

They described him as bald on top with grey sides and a medium build, saying he might be using a crutch or walking stick.

He was last seen in a black coat and blue jeans with a grey shopping trolley and a green bag.

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