Eleven people are injured, two of them seriously, after a busy commuter train from London derailed near the south-east England town of Lewes.The South East Coast Ambulance Service said there were about 150 passengers on board the train, which departed from London Victoria station and veered off the tracks shortly before 4pm on Thursday, local time.Ian Drummond-Smith from the British Transport Police said all passengers on the train were "safely evacuated" after was declared as a "major incident".Footage from the scene in East Sussex showed at least three overturned carriages and paramedics on site.The cause of the incident remained unknown.Passenger Rob Bradley said the train began rocking as it picked up speed My laptop, my AirPods, our bags," Mr Bradley told the BBC.He could then see the car behind had flipped on its side and slid down an embankment into a lower field.Mr Bradley said he and his daughter were fine but he could see other passengers in one of the flipped cars with blood on their heads and clothing.Another passenger told him they had been cut when a window shattered."Deeply concerned of reports of a derailment involving a Southern train," Transport Secretary Heidi Alexander said on X. "Grateful to emergency services who are on the scene supporting those impacted."The accident involved a train from Southern Rail, which connects areas south of London to the capital.Train accidents, particularly fatal ones, are relatively rare in Britain.A train driver was killed and dozens of people injured when two trains collided north of London in June.Four people suffered minor injuries in a train derailment due to a reported landslide in remote north-western England last November.AP/AFP