"Activists are thought to have been inspired by a viral documentary that tried to highlight China's toxic smog problem but was censored by Beijing"

"BEIJING --  Police in northern China have arrested two citizen activists who took to the streets with placards reading: 'The government has a duty to control smog'.

Feng Honglian and Zhang Hui were taken into custody on Sunday, one day after China's environment minister promised to 'guarantee the public's rights to supervise the fight against air pollution'.

Earlier in the day, the pair had been among a small group of activists who held an anti-pollution protest in Xi'an, the capital of Shaanxi province.

Photographs posted on the internet show the campaigners wearing face-masks and holding posters with slogans including: 'Smog causes cancer and harms everyone'.'

Tom Phillips reports for the Telegraph March 9, 2015. [2]