Estonia has been closing its border with Russia since December 1 after an attempt to set fire to a defense plant.
The reason was an attempt to set fire to the building of the defense industrial plant Threod Systems in Vimsa, which, according to the Estonian authorities, was organized by the GRU.
Estonian Prime Minister Kristen Michal said the attackers had been arrested. The border closure is supposed to strengthen the country's security and limit Russia's opportunities for hostile activity.