"Both drivers of the Polish bus that swerved off the motorway near Breznicki Hum on Saturday were killed in the accident, and autopsies were performed on all the victims," state news agency Hina said on Monday citing Darko Galic, spokesman for the County State Attorney's Office in Varazdin.

Hina did not clarify whether the autopsies helped get any new information.

Twelve people were killed and 32 were injured in the accident. They are all Polish nationals.

“Autopsies were performed on the victims and information is being collected about the bus route and the events that preceded the accident. The most important information is that concerning the autopsy of the driver,” Galic said.

He added that both bus drivers were killed in the accident and that it was established beyond doubt which one had been driving the bus at the time of the accident.

“The driver was wearing a seat belt,” Galic said.

The State Attorney’s Office needs to determine whether a criminal offense was committed and who committed it, after which a decision will be made because criminal proceedings cannot be conducted against a person who is not alive.

“After collecting all the data, the State Attorney’s Office will decide whether the proceedings will be conducted here or in Poland, taking into account that all victims are Polish nationals,” Galic said.

There were 42 passengers on board the bus that was traveling from Warsaw for a pilgrimage to Medjugorje in Bosnia and Herzegovina.