Poland officially accuses Russian intelligence of deliberately starting a massive fire that destroyed a Warsaw shopping mall last year.
Prime Minister Tusk declared that the arson attack at the Marywilska shopping centre was ordered by Russian special services and evidence is concrete.
Several suspects are already in custody, with others identified and being actively pursued by Polish authorities in a detailed investigation.
Moscow has yet to respond to these serious accusations, which are part of a pattern of alleged Russian sabotage in Europe.
