Parcels containing animal eyes have been sent to six Ukrainian embassies in Europe, its foreign ministry says.
Spokesman Oleg Nikolenko said the “blood-soaked” packages were found in Hungary, Italy, Netherlands, Poland, Croatia, and Austria.
It is not clear who sent the packages to the embassies and consulates.
Foreign Minister Dmytro Kuleba believes a “well-planned campaign of terror and intimidation of Ukrainian embassies and consulates” is taking place.
Two days ago an employee was injured after a letter bomb exploded at Ukraine’s embassy in Madrid, Spain – one of a series of alleged incidents.
Mr Nikolenko referred to a number of others in a statement released on Facebook, including that the entrance to the premises of the Ukrainian ambassador to the Vatican have also been vandalised.
What’s more, he added, the embassy in Kazakhstan has received a spoof bomb threat, while the embassy in the USA has received a letter containing a photocopy of an article critical of Ukraine.
“The letter came synchronously with others from the territory of one European country,” Mr Nikolenko said. “Ukraine is working with foreign law enforcers to investigate all the threats, identify those implicated and bring them to account.”
The six packages delivered to the European embassies and consuls, he added, “were impregnated with a liquid of characteristic colour and had a corresponding smell”.
Mr Nikolenko also said Ukrainian consulates and embassies have stepped up security measures, following Dmytro Kuleba’s instructions after the blast in Madrid.
Spanish police confirmed they received a report about the explosion at around 13:00 local time (12:00 GMT). As yet, no-one has said they are behind the blast, and it is unclear whether any of the incidents are related.
Later on Wednesday evening, a second “suspicious postal shipment” was intercepted at the headquarters of military equipment firm Instalaza in Zaragoza, the interior ministry said.
Then, on Thursday morning, letter bombs arrived at the defence ministry and at an air base in Torrejon de Ardoz, just outside Madrid.
Another device was also sent to the US embassy.
“The characteristics of the envelopes, as well as their content, are similar in the five cases,” Spain’s Secretary of State of Security, Rafael Perez, told journalists.
“There are signs that indicate that the letters came from Spanish territory, but I insist we must be prudent…we are at the beginning of the investigation.” (BBC)