ULAN BATOR - Mongolia's Ecological Police Department on Tuesday issued a bubonic plague warning amid fear of the spread of this disease in Ulan Bator.

The warning came after 22 dead marmots were discovered and seized by police last week from a vehicle travelling from western provinces to the capital city of Ulan Bator.

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Currently, relevant officials of the country, including police officers and inspectors, are working 24 hours at all checkpoints on the outskirts of Mongolia's capital to prevent the spread of bubonic plague.

A total of 137 soums (administrative subdivisions) of 17 provinces in Mongolia are now risk areas of bubonic plague, according to the country's National Center for Zoonotic Diseases.

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The bubonic plague is a bacterial disease that is spread by fleas living on wild rodents such as marmots, which can kill an adult in less than 24 hours if not treated in time, according to the World Health Organization (WHO).