Detectives are looking for a man who absconded from a secure mental health facility five days ago.
Terrence Mayes, 41, was being detained under the Mental Health Act at the hospital in Southall before breaking out on Monday.
Police have appealed for help finding him, while warning the public not to approach him if he is spotted.
A Metropolitan Police spokesman said: “Despite an extensive investigation, officers have been unable to locate Terrence Mayes and are now appealing for the public’s help.
“He has links to Wembley, and it is thought likely that he will be in the west London or north-west London areas.”
“Have you seen him, do you know where he is, or do you have information that might help officers locate him?”
Police ask anyone who sees him to call 999 and quote reference 5425/22Sep.