On Sunday, the Czech weekly investigative magazine Respekt reported that a Russian assassination plot had been underway earlier in April. Citing “sources in Czech intelligence”, Respect said a Russian citizen carrying a diplomatic passport had arrived in Prague in early April. The man was allegedly had with him a suitcase with a concealed quantity of ricin —a deadly toxin. His alleged mission was to assassinate at least two high-profile Czech mayors, Prague mayor Zdeněk Hřib and Ondřej Kolář, who is the mayor of a large municipality in the Czech capital.

The two men are known for being fervently anti-Russian. Earlier this year, Hřib led a nationwide effort to rename the square in front of the Russian Embassy in Prague after Boris Nemtsov, a Russian opposition activist who was gunned down in Moscow in 2015. Kolář has been advocating for years for the removal of Soviet-era statues from Prague’s public spaces.

According to Respekt Hřib filed a police complaint during the first week of April, alleging that someone had been following him near his residence. He was then placed under police protection, after —according to him— the police determined that his complaint was grounded in reality. He has since refused to state the precise reasons for the police protection —which means that the allegations in Respekt remain unconfirmed.

On Tuesday, Kremlin spokesman Dmitry Peskov dismissed the Respekt allegations as “fake”. He added that the Russian government “doesn’t know anything at all about this [police] investigation” in Prague. However, the Czech Ministry of Foreign Affairs said on Tuesday that “there would be consequences” if the two men were harmed in the coming weeks.