A man was detained in Spain suspected of sending letters with explosives, including the address of the Embassy of Ukraine.

According to El Pais, police officers arrested a 74-year-old man in Miranda de Ebro, Burgos province. He is allegedly the author of six letters with explosives that caused an anti-terrorist alert in late November and early December.

Among the recipients was the Prime Minister of Spain, Pedro Sánchez, and the embassies of Ukraine and the USA in Madrid.

The arrested man, a Spanish citizen, allegedly acted alone and is not connected to any group. Currently, the police are searching his dwelling in Burgos.

The outlet La Sexta reports that the arrested man was an official in the city council of Vitoria, near Miranda de Ebro. He currently lives alone with no known affiliation to any political group.

Since the postal service cannot track its shipments, the police resorted to the traditional method. They collected images from the cameras of the post offices from which the packages had been sent. They located the letters on the records and, with the help of this information (date and time when it happened), tried to reconstruct the route that led them to Castile and León (Valladolid and Burgos).

The envelopes were the most characteristic element of the shipments. These envelopes were 20x15 but with a very special cut. The police managed to find a company that distributes these envelopes online. The police checked all the buyers in different provinces of Spain and found a buyer in Burgos.

Having already zeroed in on this individual, the police found that he had also purchased anniversary stamps online and other materials present in the letter bombs. All these testimonies and evidence led the police to conclude that the currently detained man was responsible for sending the letters.

In December, police said six packages with explosives were sent from the northern city of Valladolid. It is about 130 km from Burgos.

Most packages were neutralised, while an employee of the Embassy of Ukraine was slightly injured while opening a letter bomb.

After that, Ukrainian embassies in 12 countries, including Spain, received letters with threats, which the Ministry of Foreign Affairs called "a well-planned campaign of terror."

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