Updated

Chinese authorities say 14 people were killed when a truck carrying stones overturned and dumped its cargo onto a roadside activity center.

The central government's State Administration of Work Safety said Friday's accident in the southern province of Guizhou was apparently caused by brake failure.

The incident occurred on the eve of the three-day May Day holiday, during which millions of Chinese are expected to travel within China and abroad. Traffic police in recent days have been cracking down on overloading, poorly maintained vehicles and drunk driving in an effort to avoid the carnage regularly seen on Chinese highways during public holidays.

Those efforts have been intensified with the rise of private car ownership among China's growing middle class, which now drives more than 172 million vehicles.