Police have set up checkpoints around Ziketan in Qinghai province, a town of 10,000 people, which has been put under quarantine after at least a dozen people caught the lung infection that can kill within 24 hours if untreated.
Some people tried to leave the quarantined area Monday evening, mostly by foot, after the third death was reported, two residents reached by The Associated Press said.
"A lot of people ran off last night when they heard that another person died of this plague. They are mostly from other provinces," a local food seller, surnamed Han, said Tuesday. "They headed back home with food, water and their donkeys."