A "driver's guardian" seat being prepared by two bus company employees on a bus in Qingdao. [File Photo/IC]

Seats have been set aside on public buses in two cities in China for passengers willing to volunteer to intervene in passenger disputes with bus drivers, reports China National Radio.

Dubbed "driver's guardian" seats, the initiative started in the city of Qingdao in Shandong province before being taken up in Zhengzhou, the capital of Henan province. It follows an attack by a passenger on a bus driver in Chongqing, which led to the vehicle running off a bridge and plunging into a river. All 15 people on board were killed.

No clear rules have reportedly been set for passengers using the reserved seat, but one bus driver in Qingdao told China National Radio most of the people who used the seat were young people.

The introduction of the "driver's guardian" seats has stirred discussion on social media in China. Some have applauded the move as worth trying, as it raises community awareness of the issues of violence against bus drivers. But others are concerned that the volunteers are putting themselves at risk of injury in case of an incident, and it's not clear whether they'll be blamed if they fail to stop a dispute.