An off duty officer from Bromley Police was involved in the arrest of a man allegedly armed with a knife aboard a Beckenham train "packed full of children".

The female PC had been travelling home yesterday (September 28) aboard the train with her housemate, a colleague from Lambeth police, when they reportedly spotted a man in possession of a knife.

The pair were able to coordinate with British Transport Police to facilitate the man's arrest.

A spokesman for Bromley Police took to the force's Twitter page to recognise the efforts of the dedicated duo.

The spokesman tweeted: "On their way home this evening our very own PC1227SN & her housemate PC1119AS from @LambethMPS witnessed a male in possession of a knife on a #Beckenham train full of children - thanks to their actions this man is now in custody courtesy of @BTPLondon.

"#NeverOffDuty."