The string of suspicious packages follows six high-profile Spanish officials and institutions receiving flammable letter bombs on Wednesday.
Ukrainian embassies and consulates in six European countries have been sent packages containing animal remains, Kyiv's foreign ministry has said.
The consulate in Brno, in Czechia and a neighbouring children's nursery, were evacuated after another such package was received.
Ukraine's Foreign Ministry spokesperson Oleg Nikolenko said the parcels contained animal eyes, and that it was believed that they were part of a well-planned campaign of terror and intimidation.
Parcels containing animal eyes were also sent to embassies in Poland, Hungary, Croatia, Italy and the Netherlands.
One containing a flammable powder was sent to the Ukrainian Embassy in Madrid. It ignited upon opening on Wednesday and injured a security officer.
And Ukraine’s ambassador to the Vatican, Andrii Yurash, said the entrance to his Rome residence was vandalised with what he believed were animal faeces on Thursday.
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