Police are offering a 3 million ruble ($95,000) reward for information that could lead to the capture of the gunman who killed six people in a shooting spree in downtown Belgorod on Monday.
The suspected shooter, 32-year-old Sergei Pomazun, is still at large, despite earlier reports that he had been caught. Police have told Belgorod residents to stay indoors, warning that Pomazun, who has previous convictions, is believed to be heavily armed and dangerous.
Police have also contacted their Ukrainian colleagues for assistance, as Belgorod is located less than 100 kilometers from the border with Ukraine.
Despite earlier reports that Pomazun had made it into Kharkov, Ukraine's Interior Ministry issued a statement Tuesday saying the suspect had not entered the country and that 20 extra police squads were monitoring the border.
Pomazun reportedly opened fire first in a hunting store and then on a main city street. Five of his victims were killed on the spot, and a 16-year-old girl died of her injuries in the hospital late Monday.
Police say Pomazun's motive may be a refusal by salesmen to let him purchase weapons in the hunting store.
As many as 1,200 law enforcement officers are now searching nearby regions for evidence as to Pomazun's whereabouts, RIA-Novosti reported, citing police.
Pomazun faces up to life in prison on three separate charges, including the theft of weapons and ammunition, the use of stolen weapons to inflict injury and the murder of six people.
President Vladimir Putin is aware of the tragic shooting and following developments, according to his official spokesman, Dmitry Peskov.
Belgorod Mayor Sergei Bozhenov has declared Tuesday and Wednesday days of mourning for the victims.