Four people were killed and 13 others injured after a farming vehicle veered off a road into a river in Xi'an, capital of northwest China's Shaanxi province, local authorities confirmed Saturday. The accident happened around 5:40 p.m. Friday in the city's Chang'an district, Xinhua quoted publicity officials as saying. The three-wheeled vehicle went out of control and overturned into a roadside river, according to the officials. There were a total of 18 passengers on the vehicle. The injured were sent to nearby hospitals and the driver is being questioned.