Lennox Standing has not been seen for five days – the last sighting was on Friday, January 3.
He is believed to now be in the Cleveland area.
A Cleveland Police spokesperson said: “Have you seen missing Lennox?
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“Lennox Standing, 15, hasn’t been seen since Friday 3rd January.
“He was last seen in Durham, but is now believed to be in the Cleveland area.
“Please call 101 if you see him or know where he is.”
