The number of missing persons following the collapse of an under-construction bridge pier has risen to 11 in southwest China's Chongqing Municipality, local government said Saturday.

The No. 4 pier of a bridge across the Yangtze River in Fengdu County collapsed and became submerged in water at about 10:30 a.m. Saturday, said the Fengdu County government.

The accident happened after a beam on a floating crane fell and impacted steel cofferdams, which supported the pier.

Ten construction workers and one resident went missing after the accident. The resident, who was washing clothes at the riverside, was swept away by waves generated by the pier collapse.

Two people sustained minor injuries and are being treated in a hospital.

Sixteen vessels and 141 rescuers are searching the river for the missing people.

Construction has stopped and the cause of the accident is still being investigated.