Spain has ordered increased security at government buildings and embassies after the discovery of six letter bombs and incendiary devices over the past seven days, including one that exploded at Ukraine’s embassy in Madrid on Wednesday and another that was detected at the US embassy on Thursday.
Devices have also been sent to the prime minister, the defence ministry, an arms company that makes rocket launchers donated to Kyiv, and a military airbase near the Spanish capital.
Spain’s secretary of state for security said initial analysis suggested the packages had been sent from within Spain.
“They’re similar-looking brown envelopes,” Rafael Pérez said in Madrid on Thursday. “We’re at the early stages of our investigation. While there are signs that they came from Spanish territory, let’s be prudent.”
Pérez said there were not yet sufficient reasons for raising the terrorism threat level, and the government was not aware of similar packages being sent to other countries.
Spain’s highest criminal court, the audiencia nacional, is leading an investigation into the matter, and experts will be examining the envelopes for DNA and handwriting comparison.
The Ukraine embassy letter bomb exploded when it was opened by an employee on Wednesday, causing minor injuries to the worker’s hands and leading Ukraine to warn its diplomats to bolster their security precautions.
The second, discovered hours later at Instalaza, a weapons company in Zaragoza, in the Aragón region, that manufactures C90 rocket launchers, was deactivated by bomb squad officers.
In the early hours of Thursday, police were called to the Torrejón de Ardoz airbase after security systems there detected a suspicious package.
On Thursday morning, it emerged that a letter containing “pyrotechnic material” and addressed to the prime minister, Pedro Sánchez, had been intercepted on 24 November at Moncloa Palace, his official residence.
Shortly afterwards, the defence ministry said a suspicious package had been detected at 9am, prompting a call to bomb squad officers. It was addressed to the defence minister, Margarita Robles. Another device in a similar envelope was found at the US embassy at 12.30pm on Thursday and “neutralised” by police, according to the interior ministry.
The ministry said the discovery of the Moncloa package had led it to order an immediate tightening of security at public buildings, especially when it came to postal checks.
A spokesperson for the ministry said X-rays had shown that the envelope sent to the European Union satellite centre at the Torrejón de Ardoz base contained some kind of mechanism.
“Officers from both the national police and the civil guard went to the base to seal off the area, and police investigators are analysing the envelope, which was addressed to the satellite centre,” he said.
Preliminary investigations suggest a link between the first two letters as both envelopes bore the same return address.
Ukraine’s ambassador to Spain, Serhii Pohoreltsev, said the first suspicious package had been addressed to him and was handed to the embassy’s commandant.
“The package contained a box, which raised the commandant’s suspicions and he decided to take it outside, with no one in the vicinity, and open it,” Pohoreltsev told the Ukrainian news site European Pravda.
“After opening the box and hearing a click that followed, he tossed it and then heard the explosion … Despite not holding the box at the time of the explosion, the commandant hurt his hands and received a concussion.”
The employee was taken to the Nuestra Señora de América hospital and discharged shortly afterwards.
Rosa Serrano, the Spanish central government’s delegate to Aragón, said the arms company in Zaragoza contacted the police after receiving a letter it had not been expecting.
“It was an envelope measuring 10cm by 15cm and a little more than a centimetre thick,” Serrano told the SER radio station. “The envelope was examined and X-rayed and found to contain a small charge that was designed to cause an explosion when it was opened. We don’t know what type of explosive it was.”
After the discovery of the first package, Dmytro Kuleba, the Ukrainian foreign minister, urged all of the country’s embassies to tighten their security measures.
The minister also urged his Spanish counterparts to take urgent measures to investigate the attack, adding that whoever was responsible “will not succeed in intimidating Ukrainian diplomats or stopping their daily work on strengthening Ukraine and countering Russian aggression”.
Russia’s embassy in Madrid released a statement on Thursday expressing its “total condemnation … [of] any threat or terrorist act – especially those directed at diplomatic missions”.
Reuters contributed to this report