Chinese authorities have blamed the driver of a sightseeing bus for Thursday's fatal accident that killed three Japanese tourists in the eastern Chinese province of Shandong, Chinese police sources said Saturday.
The driver, Hao Ruizhao, 53, has been detained for questioning.
Investigators believe Hao was not concentrating while driving at high speeds on an expressway after sunset with reports of fog in the area.
"The driver is entirely responsible for this accident," a police spokesman in Zibo said.
The bus, carrying 20 mostly elderly Japanese tourists and a Japanese tour guide, left the city of Qingdao around lunchtime Thursday and headed toward Mount Tai, a popular tourist attraction. It collided with the rear of a truck traveling in the same direction and careened off the highway into a ditch.
Police said Hao veered sharply to the left after hitting the truck and, when his vehicle hit the center divider on the highway, suddenly turned to the right. The bus fell into a 1.5-meter-deep ditch beside the road.
Police believe Hao was "empty headed" as he drove the bus at 110 kph, the standard speed limit on China's expressways.
The accident occurred at around 6:30 p.m. local time. It was dark at the time, and some witnesses reported seeing fog in the area.
The relatives of two of the Japanese tourists killed in the accident -- Toyo Mori, 62, of Kobe, and Miho Izumi, 42, of Nara -- were scheduled to meet the tour guide, who survived the accident, at a Zibo hotel on Saturday.
Family members of the 17 Japanese tourists who survived were also expected to arrive in Zibo on Saturday afternoon.
The Japanese Embassy in Beijing said one passenger is in serious condition while the others sustained only slight injuries.