The Prosecutor General's Office is considering two main explanations for the traffic accident that killed national guardsmen in Donetsk region on Monday, which led to the deaths of 12 people, either violation of road traffic regulations or a malfunction with the bus that carried the troops.

Prosecutor General Vitaliy Yarema reported to Ukrainian President Petro Poroshenko on the investigation into the accident on Tuesday, the president's press service reported.

According to the prosecutor's office, the KrAZ truck driver was sober.

"Vitaliy Yarema stated that 12 soldiers died in the accident. In addition, the sobriety test of KrAZ truck driver was negative. According to the Prosecutor General, the investigation is being conducted and the versions of the accident's causes are being considered, including two main ones – violation of road traffic regulations and malfunction of the bus carrying troops," the press service noted.

According to the statement, the president has ordered that a hotline be set up in the Interior Ministry that "has to report on the condition of the servicemen, who were in the accident."

In addition, Poroshenko ordered the creation of a special commission headed by Deputy Chief Military Prosecutor General at PGO Maksym Yakubovsky to determine the reason for the accident, and discover those culpable for the accident and the deaths. Five PGO investigators were assigned to the commission.

"Petro Poroshenko has ordered to hold an immediate press conference to inform the public on the peculiarities of the tragedy," the press service noted.

The head of state also expressed his condolences to the relatives of the deceased servicemen.

According to the press service of Donetsk Regional State Administration, the region's governor Oleksandr Kikhtenko has visited the guardsmen injured in the accident.

At night, doctors performed 16 operations. In the morning, 17 servicemen were brought to Kharkiv military hospital. As of 1200, four guardsmen were in a hospital in Artemivsk. Their condition is rather severe. All of them will be transferred to Kharkiv today.

The governor ordered the delivery of food to Artemivsk central district hospital, as those wounded from the military action zone are brought there, according to the press service of Donetsk Regional State Administration.