Several outlets describe a crash that authorities say is Britain’s worst rail disaster in about 20 years. The incident occurs shortly after 5pm on June 19, 2026, when a Luton Airport Express service runs into the back of a stationary train that is travelling towards London. The reports present the event as a chain of circumstances leading to the collision, noting that the key point is the late-afternoon timing and the alignment of the moving service behind a train that is already stopped on the track. According to the accounts provided, the impact is severe enough to be characterised as a major rail disaster, with the investigation and public explanations focusing on how the moving train comes into contact with the stationary one. The available summaries do not specify the cause in detail, the exact location on the route, or any confirmed casualties or service disruptions beyond the framing of the incident as a worst-in-two-decades event.