A man claimed to be armed with an explosive device walked into Uxbridge police station on Sunday (November 20).
Armed police were in a two-hour stand-off with a man after he entered the building in Warwick Place at around 11.50pm.
Negotiators and specialist officers joined armed police at the incident.
Negotiations with the man resulted in him voluntarily surrendering himself to police in the early hours of this morning at around 2am (November 21).
There were no reported injuries and the device was declared "non-viable."
A Metropolitan Police spokesman said: "At 11:51pm on Sunday, 20 November, a man entered Uxbridge police station and stated that he was armed with an explosive device.
"Following negotiations, the man voluntarily surrendered to police at 2am.
"There are no reported injuries.
"The device the man claimed to possess has been declared as non-viable."
A man in his 30s has been arrested on suspicion of threatening to cause an explosion, criminal damage and possession of class A drugs.
He remains in custody at a west London police station.
Police enquiries continue.
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