Twenty-two people, including an associate professor, stood trial Wednesday for pruriency offenses in a closed-door court session in east China's Nanjing City.

Qinhuai District prosecutors said the 14 men and eight women met through an online chat room and engaged in dozens of group sexual activities between 2007 and 2009.

Under China's criminal law, assembled pruriency involves organizing and participating in group sexual activities at the same time and place.

If convicted, the suspects may face jail terms of up to five years.

The associate professor, surnamed Ma, from a Nanjing university set up the chat room and engaged in 18 partner-changing activities, prosecutors said.

Ma described the activities as spouse-swapping parties.

There were only two married couples in the group, according to prosecutors.

Some of the parties were held in hotels while others were held at Ma's residence, the Qinhuai District Court heard.

The trial has spent time considering privacy issues, and no verdict was handed down Wednesday.