A critical incident has been declared in north-east London, MP Wes Streeting says, amid reports of several people being stabbed near a Tube station.
Mr Streeting, MP for Ilford North, wrote on X, formerly Twitter: "A critical incident has been declared in Hainault.
"There are station and road closures in place," he said.
Police say a man has been arrested, adding: "Please follow the instructions of police officers on the ground."
Footage shared on social media appeared to show a man with a machete in Laing Close, close to the Tube station.
Transport for London (TfL) said Hainault London Underground station was closed due to a police investigation in the area.
Mr Streeting added: "The police, ambulance service and fire brigade are responding.
"I would urge people not to speculate until details are confirmed or post footage on social media."
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