(Refiles to remove extraneous number in the first paragraph)
* Authorities found 44 bodies from the bus crash
* Victims suffocated from heavy smoke
* The bus burst into flames after hitting traffic barrier
SOFIA, Nov 25 (Reuters) - Bulgarian investigators said on Thursday that human error was the most likely cause of a bus crash that killed more than 40 people.
The bus was carrying tourists, including children, from North Macedonia returning from a weekend trip to Turkey. It crashed in flames on a highway in western Bulgaria before daybreak on Tuesday.
Investigators have ruled out a terrorist act or that additional tubes with fuel on aboard could have caused the deadly fire. They also established there had been no blast.
"For the time being, the leading and main version is the one of a human mistake," the head of Bulgaria's National Investigation Service, Borislav Sarafov, told a news briefing on Thursday.
"The autopsies indicate that all victims have died mainly from suffocation following the fire, and not from injuries from the crash or from injuries from a blast," he said.
Investigators are examining whether poor lane marking, lack of proper signs and reflectors, and poor organisation of highway traffic could have contributed to the accident.
"Our opinion is that the traffic barrier on which the bus strung first is not only not useful, it is dangerous for the traffic and it has actually helped for the accident," Sarafov said.
The bus has hit a traffic barrier on the right side, ripping it off and catching fire from the friction, then swerved to the left before stopping in the traffic barriers that separate the highway lanes, investigators said.
"Witnesses have said that immediately after the first hit fire broke out and the bus was quickly filled with smoke," said lead investigator Marian Marinov.
"No one could exit from the first door because of the strong fire there. All gathered in front of the rear door, but it was blocked by the traffic barriers which stopped the bus," he said.
Authorities reported 45 victims from the accident, but investigators have found 44 bodies. They were trying to establish whether one passenger who was on the manifest had moved to another bus that were part of the same weekend trip, or had survived the crash.
One survivor, who broke a window at the back of the bus, testified that eight people jumped out of the burning vehicle, said Siyka Mileva, spokesperson for the chief prosecutor. Only seven passengers were rushed to hospital.
Bulgaria is sending two officials to North Macedonia on Thursday to receive DNA samples from the relatives, needed t identify the victims, Sarafov said. (Reporting by Tsvetelia Tsolova; Editing by Angus MacSwan)
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