On March 30, 2018, a fast train (FT) № 8613 composed by 4 coaches, 16 axles, 164 tons, serviced by electric locomotive № 43309.4, has departed Sofia station for Burgas station. The route of train movement is Sofia - Plovdiv - Dimitrovgrad - Stara Zagora - Burgas. At Plovdiv Station the locomotive and transport brigades are shifted according to the schedule. During the travel, the train has changed the direction of traffic at Dimitrovgrad station. Duty staff at the stations along the route hasn‘t noticed anything unusual. The same is confirmed by the locomotive and transport brigades, who have served the train from Sofia station until it arrives at Konyovo station.
The train leaves Nova Zagora station at 19:51h and arrives at Konyovo station at 19:59h (as evidenced by Konyvo Station II-76 log-book and the locomotive speed belt). According to "Plan II-24", the train is admitted on second reception and dispatch track and has to spend 5 minutes for a meeting, according to schedule for trains movement (STM), with the transiting fast train №8632 (Figure 1). After FT № 8613 stops at the station, the duty head of movement sees smoke coming out between 3rd and 4th coaches. Soon after, a fire occurs at the end of 3rd coach. For the situation at the station, the duty head of movement informed the train dispatcher, who in turn ordered the duty head of the movement at Kermen station to hold FT № 8632 at Kermen station.