Shocked diners were locked in a Nandos in east London as armed police swarmed a nearby apartment block amid a suspected hostage situation.
The restaurant was advised to lock its doors as police descended on the scene in Romford Road, Stratford on Thursday.
The man, who was allegedly holding a woman against her will, was later arrested on suspicion of false imprisonment.
A manager for the restaurant told the Standard: "We were advised by police to lock the doors.
"The situation went on for an hour and a half but we were only closed for around half an hour."
Customers inside the restaurant at the time described on social media how the incident unfolded.
One wrote: "Got locked in a Nandos and had to leave through the emergency exit. 15 armed guards."
Another said: "There is a bit something going off here in Stratford, London. About 15 armed police i've seen and area been cordoned off."
A Scotland Yard spokesman said: "Police were called at 1.33pm to reports of a man believed to be in possession of a firearm holding a woman against her will at a residential address in Romford Road.
"Officers, including armed officers, attended and found the victim safe and well.
"A man was arrested on suspicion of false imprisonment. He has been taken to an east London police station.
"No firearm has been recovered at this stage, however officers are continuing to search the address. A cordon is in place."
