Russia has been accused of sending "bloody" packages containing animal eyes to Ukrainian diplomats across the globe.
Ukraine said multiple European embassies have received the envelopes containing the gruesome body parts, including its embassy in Madrid, which also received a letter bomb earlier this week.
Ukraine's Minister for Foreign Affairs, Dmytro Kuleba, was asked by CNN who he thought was behind the letters.
He said: "I feel tempted to say, to name Russia straight away because first of all you have to answer the question, who benefits?"
“Maybe this terror response is the Russian answer to the diplomatic horror that we created for Russia on the international arena, and this is how they try to fight back while they are losing the real diplomatic battles one after another.”
Authorities say the packages are soaked in a liquid with a distinctive colour and smell and have also been sent to embassies in Hungary, the Netherlands, Poland, Croatia and Italy, to general consulates in Naples and Kraków, and the consulate in Brno in the Czech Republic, according to Ukraine’s foreign ministry spokesperson, Oleg Nikolenko.
Mr Kuleba said he thought that Russia was either directly responsible or that someone "who sympathises [with] the Russian cause and tries to spread fear" was.
Russian foreign ministry spokesperson Maria Zakharova responded to his claims with a single-word comment: "psycho."
CNN was able to see a photo of one of the letters and said it appeared to contain the eyeball of a pig inside a padded envelope.
On Friday, Ukrainian consulate staff in Brno, a city in the southeast of the Czech Republic, were evacuated after receiving a suspicious package containing animal tissue.
Mr Nikolenko also said the entrance to the Ambassador’s residence in the Vatican was vandalized and the Ukrainian Embassy in Kazakhstan received an unverified report of a bomb threat.