Shaun Berry, from Bury, has not been seen since June 26.
The 16-year-old - who is believed to be in Burnley - is described as a white male, 5ft 7in tall, of slum build with dark brown curly hair.
He has blue eyes and was last seen wearing a black tracksuit.
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If you have any information about Shaun's whereabouts, call 101 quoting LC-20210627-1462.
For immediate sightings call 999.
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