All residents in China's largely Muslim region of Xinjiang must hand in their passports to local police stations for "examination and management", according to Global Times, a state-funded newspaper .
"Anyone who needs the passport must apply to the police station," an anonymous police officer in Aksu prefecture told the paper on Thursday, adding that the policy had been implemented throughout Xinjiang.
The Global Times article followed numerous reports of tightened passport controls in cities across the region.
In June, local state-run media reported that the mostly Kazakh residents of a Xinjiang border district had to give police DNA samples, fingerprints, voiceprints and a "three-dimensional image" in order to apply for certain travel documents, including passports.
A Xinjiang official told the Global Times that the new tightening of policy was intended to maintain social order in the region.