The search is on for two missing residents from Ealing and Harlesden.
The appeal urged anyone who has seen or heard from the "missing and vulnerable" 35-year-old to come forward and call 101.
A social media appeal was tweeted by Ealing MPS at 2.34pm.
It said: "Daniel Tailor is 35, missing and vulnerable.
"If you see him or know where he is, please call 101. Thank you."
Police from west London are also searching for Simon Beeput, who has gone missing from the Harlesden area.
Officers have urged anyone who has seen him to call 101 and quote CAD 3215/31.
The twitter appeal was launched by Brent MPS at 1.57pm on Thursday (August 31).
It said: "Simon Beeput has gone missing from Harlesden area.
"If you spot him please call 101 and quote CAD 3215/31. Thank you."
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