A dog is suspected of being the source of a pneumonic plague outbreak in the remote town of Ziketan in Qinghai province, AFP reported, citing state media. The dog was thought to have been owned by the initial victim, a 32-year-old herdsman. Professor Wang Hu, director of the Qinghai disease control bureau said the dog contracted the disease after eating a plague-infected marmot and the herdsman was in turn probably bitten by fleas and infected when burying the dog. The World Health Organization says the bacteria which causes the plague is endemic in some rodents in the region, including marmots. The outbreak has killed three people and left 10,000 quarantined in the town. State media said currently one person was under full medical quarantine and eight others were infected. Most of them were relatives of the herdsman.