ZAGREB, Croatia (AP) — A bus swerved off a highway and crashed in Croatia early Sunday after the driver apparently fell asleep, killing 10 people and injuring at least 44 others — some of them seriously, authorities said.

The crash happened at around 6 a.m. (0400 GMT; 12 a.m. EDT) near the town of Slavonski Brod on the highway between the capital, Zagreb, and the Serbian border.

Authorities said after an investigation that the driver of the bus had been arrested after he apparently lost control over the vehicle after briefly falling asleep.

“He said he fell asleep for a moment,” local deputy prosecutor Slavko Pranjic said, according to Index news portal in Croatia.

Photos from the scene showed the bus on the side in the grass near the edge of the road. Firefighters and rescuers could be seen around the bus while traffic on the highway was halted for hours before the bus was removed and one lane reopened, local media said.

Police said the bus had Kosovo license plates and was on a regular route from Germany to Kosovo capital Pristina, which is located south of Serbia.

Officials said the bus was carrying 67 passengers, including children, and two drivers, one of whom died in the crash. Local police chief Franjo Galic described the crash as “one of the worst accidents I have ever seen."

The 44 injured were transferred to hospitals in the area. Slavonski Brod hospital chief Josip Samardzic said eight people had serious injuries.

Health Minister Vili Baros later said 15 minors were passengers and that one girl was seriously injured.

Croatian Prime Minister Andrej Plenkovic expressed “sadness and grief” and extended his condolences to the relatives of the people who died in the crash and the people of Kosovo.

“We hope the injured will recover,” Plenkovic tweeted.

Croatian President Zoran Milanovic also expressed condolences and wished a speedy recovery to the injured.

Kosovo sent its interior minster to Croatia, as top officials offered condolence to the families of the victims and expressed hope for the swift recovery of the injured.

President Vjosa Osmani, who is in Tokyo at the Olympic Games, extended her sorrow in a message on Facebook.

“With our heart and in spirit, we are close to the families who lost their loved ones in this tragedy," Osmani said. “It is an indescribable pain and a great loss."

Kosovo Prime Minister Albin Kurti said that “this is a tragic day for our country and for our people.”

The highway where the crash happened is a key traffic artery through Croatia which is busy over the summer because of tourism and foreign workers traveling home from Western Europe.