An online photo shows students kneeling in front of a national flag. [Internet photo]

An image of a group of school children being forced to kneel before a national flag as a form of punishment has sparked a wave of interest online and forced a bizarre flurry of differing explanations of the incident, cntv.cn reports.

Micro blogger Qinyashen posted the photo online on May 20 displaying the forced punishment at Gongyi No 4 Middle School in Henan province.

The post prompted the school to issue three different explanations within one day.

First, an officer with the school told local media the incident was fabricated and the photo was manipulated in Photoshop on May 21.

He Xianwei, a director with the school then told CNTV the children were actually cleaning floors.

Gongyi municipal press department then offered a third explanation saying that more than 20 students forgot to bring earphones when joining a listening test and they were told to do push-ups on the playground before resuming the test.

Zhao Qiuzhen, the school master then defended the previous two explanations saying they were given by teachers who were not familiar with the incident and the third one was given after investigation.