Telegraph: 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....