A man has been detained in Spain, who is suspected of sending letters with pyrotechnic materials, in particular to the address of the Embassy of Ukraine.

 This is reported by El Pais.

 According to the publication, police officers arrested a 74-year-old man in the municipality of Miranda de Ebro, Burgos province, as the alleged author of six letters containing pyrotechnic materials that sparked an anti-terrorist alert in late November and early December.

 Among the recipients were the Prime Minister of Spain, Pedro Sanchez, as well as the embassies of Ukraine and the USA in Madrid.

 According to mass media, the arrested man, a Spanish citizen, allegedly acted alone and is not connected to any group. The police are currently searching his place of residence in Burgos.

 The newspaper La Sexta reports that the detainee worked as an official of the city council of Vitoria, near Miranda de Ebro, and currently lived alone, with no known affiliation to any political group.

 Since the postal service does not have a system to track its shipments, the police resorted to the traditional method. They collected images from the cameras of the post offices from where the packages were sent. They located the packages on the records and with this information (the date and time 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, as they were ordinary envelopes, and with very special characteristics. These were envelopes measuring 20x15, but with a special cutout. The police managed to find a company that distributed these envelopes over the Internet. The police checked all the buyers in different provinces of Spain in turn and found a buyer in Burgos.

 Having already zeroed in on the man, the police found that he had also purchased anniversary stamps online and other materials present in the bomb bags (apparently bearings). All these statements and evidence led the police to the conclusion that the man who is now in custody is responsible for sending the letters.

 In December, police said six packages containing explosives had been sent from the northern city of Valladolid. It is approximately 130 km from Burgos.

 Most of the packages were destroyed, while an employee of the Embassy of Ukraine was slightly injured while checking the contents of the package.

 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."