UK police and emergency crews responded Thursday after a passenger train derailed near Lewes railway station in East Sussex.

The train carried about 150 people when it derailed around 3:54 p.m. local time. Two people suffered serious injuries, while nine others suffered less serious injuries.

Emergency crews treated passengers at the scene. They also took some people to nearby hospitals for further care. Meanwhile, passengers who did not need hospital treatment went to a nearby community center for support.

One passenger described the crash as terrifying. Yana Ludwig, 56, said the train suddenly began banging and turning over. She said the carriage fell onto its side within seconds.

Fire crews also rushed to the scene. East Sussex Fire and Rescue Service sent 10 fire engines and specialist rescue teams. Crews helped passengers leave the train and supported other emergency workers.

Meanwhile, UK Transport Secretary Heidi Alexander said she was deeply concerned. She thanked emergency crews and rail workers for helping passengers.

Officials have not yet found the cause of the derailment. However, the Rail Accident Investigation Branch sent investigators to the site. The team will collect evidence and examine what happened.

The crash also caused major rail disruption. National Rail warned passengers to expect delays for several hours. In addition, no trains can travel through Lewes or Haywards Heath until further notice.

Southern Rail also told people not to travel. The company closed all lines through Lewes while emergency crews and rail engineers inspect the railway.

The crash happened during a heatwave in southern England. Temperatures reached 35 degrees Celsius, or 95 degrees Fahrenheit, in some areas. Earlier, the heat had already caused cancellations and speed limits on some train services.

The Transport Salaried Staffs’ Association also expressed concern for passengers and rail workers.

The derailment marks the UK’s second serious train crash in two months. In June, two passenger trains collided near Bedford in south-central England. The crash killed one person and injured dozens.

Authorities continue to investigate the Lewes derailment. Meanwhile, emergency crews are working to clear the area and help restore train services.