The operator of the passenger train involved in a fatal collision in the Czech Republic this week announced on Saturday that it is to withdraw 13 Austrian-built sleeper carriages from service following the discovery of a construction fault. Four people died and a further 23 were injured in the accident in Pardubice in the early hours of Thursday morning, when a passenger train collided head-on with a freight train. The cause of the accident has not yet been established. The night express operated by RegioJet had been travelling from Prague to Košice in Slovakia. According to the emergency serv…