Ricardo Abreu, 19, was reported missing by the force on Sunday morning (June 11).
Posting on Twitter, the police said: "Ricardo Abreu, 19 years old missing from #hounslow .
"Please help us find Ricardo.
"Please call 101 with any information and quote 17MIS021512"
Hounslow Police are trying to locate a second teenager, 17-year-old Stanagul Sheengul, who was reported missing from the borough on Friday (June 9).
The force launched the appeal over social media, asking for assistance in finding the teenager.
Anyone with information relating to the whereaouts of either teenager, is asked to call police on 101.
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