MOSCOW (Sputnik) — Earlier in the day, Kohver was sentenced to 15 years of imprisonment, having been found guilty of espionage, smuggling, possession of weapons, as well as illegally crossing the state border.
"Mr Kohver’s abduction and subsequent illegal detention in Russia constitute a clear violation of international law," Mogherini said in a statement.
"The EU continues to call on the Russian Federation to act according to its international obligations, release Mr Kohver immediately and guarantee his safe return to Estonia," the statement reads.
Earlier in the day, Estonian Foreign Minister Marina Kaljurand condemned the sentencing of the Estonian Internal Security officer.
According to the Russian Federal Security Service, Kohver was detained in the Pskov Region of Russia bordering Estonia with hidden recording devices, a pistol and 5,000 euros (over $5,500 at current exchange rates) in cash.