A man is fighting for life after he was thrown from the Tube during a confrontation with another passenger, police said.
The victim suffered a severe chest injury and multiple broken ribs in the incident on a Jubilee Line train which had pulled into North Greenwich station.
He was rushed to hospital where he remains in a critical condition.
There have been no arrests, British Transport Police said.
Emergency services were called to the busy station shortly before 9pm on Friday.
A police spokesman said: "It is believed there had been an altercation between the victim and another man which led to the victim being thrown off the Tube when it arrived at platform 3 at North Greenwich station.
"The victim suffered a severe chest injury. He has been taken to a London hospital where he remains.
"Officers are working to establish the circumstances that led to the incident.
"Both the victim and the second man are described as white."
It came as a man aged in his 20s was shot dead at a block of flats in Feltham, south-west London, also on Friday night.
Anyone who witnessed the incident, or the events leading up to it, is asked to contact BTP by texting 61016 or by calling 0800 40 50 40 and quoting reference 619 of 21/06/19.
