More than a million people have been evacuated from nearly 2,500 buildings as a result of a wave of bomb hoaxes.

The false phone calls that began last month have left 170 Russian cities scrambling to deal with the evacuations, the state-run RIA Novosti news agency reported Tuesday, citing a source within the emergency services.

The anonymous bomb threats began on Sept. 10, and previous estimates had placed the number of evacuations from schools, transport hubs, malls, and government agencies at 500,000 people.