Bromley Police have hailed the bravery of an off-duty officer who pinned down a suspect after a robbery.

WARNING: Video contains explicit language

Footage being shared on Twitter shows a man pinning down a boy, who looks to be wearing a balaclava, on the pavement near to a bus stop.

The boy, 14, is laying face down on the ground while the man in plain clothes restrains him by leaning on his body and holding his wrist.

In the full clip, the man instructs onlookers to call 999 to explain what was happening, and asks them to show his police identification to the camera.

Bromley Police say the off-duty officer intervened after a robbery where a phone was stolen and threats of knives were used.

They added that he "safely restrained" the 14-year-old suspect until on-duty officers arrived.

The boy in the clip can be heard complaining about pain being caused to his wrist, and the off-duty officer tells him he can "get medical attention when the police on duty arrive".

Bromley Police said: "We’re aware of a video showing a male being detained in Masons Hill, Bromley earlier.

"An off duty officer bravely intervened after a robbery where a phone was stolen and threats of knives were used.

"He safely restrained the 14-year-old suspect until on duty officers arrived."

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