XI'AN -- A fire at a rural apartment building in Northwest China's Shaanxi province killed four people and injured 13 early Tuesday.

The fire broke out around 1:30 am at the five-story building in Yanta district, provincial capital of Xi'an, trapping 19 people, according to firefighters.

Four of the trapped were found to have died after being pulled out of the building. Among 15 people rescued alive, two sustained serious wounds, 11 had slight injuries, while two were unhurt.

The disaster was caused by an electric bike, which caught fire on the first floor of the building.