GUANGZHOU, March 5 -- Police detained two suspects on Wednesday for causing a stampede in a subway car in south China's Guangdong Province.

One of the suspects, surnamed Xu, told police that he and his friend, surnamed Yang, decided to try out the pepper stray Yang had when they were riding the subway in Guangzhou on Tuesday morning.

The spray agitated passengers in the car and their subsequent nudging and pushing against one another led to a stampede that injured four.

Police tracked down Xu and detained him, while Yang turned himself in to police on Wednesday afternoon.