A recent photo of a boy defecating inside a subway car has raised awareness among passengers about the lack of toilets in the subway lines in Guangzhou, Guangdong province.

The picture also attracted negative criticism and attention due the uncivilized conduct portrayed after it was published online early this week.

An executive from Guangzhou Metro Corp said that those who defecate or urinate in train cars and metro stations will be fined 50 yuan ($8).

He urged passengers to contact staff at the metro stations for help when they need to use the toilets urgently.

The picture has sparked controversy among passengers due to the shortage of toilets along subway lines in the city, which has a population of more than 16 million.

Han Zhipeng, a member of the Guangzhou Committee of the Chinese People's Political Consultative Conference, said that Guangzhou now has more than 100 metro stations, but that only 16 of the stations have toilets.

"The need for toilets is huge, and the subway company should build them to help address the problem, and avoid similar cases in the future," Han said.

"Mobile toilets should also be installed near metro stations," he added.

Meanwhile, Peng Peng, a researcher with the Guangzhou Academy of Social Sciences, said that parents and schools should also teach children to not urinate anywhere.