Kyle Frances was reported missing from Feltham on March 16.
Taking to Twitter, Hounslow Police said they believe the teenager could be in Isleworth .
The tweet reads: "Can you help us find Kyle FRANCIS age 15 years #missing from #Feltham, possibly in 'Isleworth.
"Please call 101 quoting ref 17MIS011600."
Anyone with information relating to the whereabouts of the teenager, should call police on 101, quoting 17MIS011600 as a reference.
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