Germany has formally accused Russia of putting an explosive drone on the tarmac at Leipzig airport, and the European Commission has promised a clear response.

The drone was found inside the secured area of Leipzig/Halle airport on the night of August 4, beside a Ukrainian Antonov Airlines cargo aircraft of the type used to fly weapons to Ukraine. Its detonator failed. The airport was shut temporarily and specialists used a robot to make the device safe. Two more drones were found near the airport later in the month, on August 14 and August 25, one of them alongside a suspected control device of an antenna and electronic components taped to a tree, according to Euronews.

The bombs in Leipzig came in a nervous month where a cahce of weapons was found earlier in Berlin and linked to Russia. Reports of hybrid attacks on various military instillations in Europe making weapons for Ukraine have been rising steadily, but now its moved on arson and sabotage to bombs and guns.

Interior Minister Alexander Dobrindt said the drone's configuration matched Russian technology used in Ukraine, and that Russian state entities had supplied the equipment and the technical expertise while leaving the execution to locally recruited operatives. The device showed a high degree of technical expertise and meticulous planning, he said, in an account reported by AP.

Europe has been accumulating arson, sabotage and drone incidents for two years while almost never naming a state, and an unattributed incident cannot be answered with sanctions. Berlin has now named one, which is what turns a police investigation into a foreign-policy instrument, and it has done so on a case where the target was the air bridge that carries weapons into Ukraine.

"With the attempted attack in Leipzig, the Russian leadership decided deliberately to do significant damage again to our already massively burdened bilateral relationship," Foreign Minister Johann Wadephul said, standing alongside Dobrindt. He called it part of a wider pattern of destabilisation, sabotage, disinformation and aggression.

Germany ordered the closure of the Russian consulate-general in Bonn from September 18 and terminated the lease on the Russian House cultural centre in Berlin. It tightened entry controls for Russian nationals, said it would press for more Russian individuals to be added to EU sanctions lists specifically over hybrid attacks, called for more pressure on Russia's shadow tanker fleet, and summoned Russia's ambassador.

European Commission President Ursula von der Leyen said she stood in full solidarity with Germany. "We will keep the EU united despite these escalating and serious acts. The German government has taken strong measures. And the message is clear: hybrid attacks will not go without a clear response," she said in remarks reported by Euronews. She was due to meet Nato Secretary General Mark Rutte on Wednesday, with EU foreign ministers to prepare further sanctions.

Rutte said the evidence was clear that Russia was responsible, and that Nato would continue to strengthen its ability to deter and defend all allies against any threat. EU foreign policy chief Kaja Kallas said Russia's aim was to scare Europe away from supporting Ukraine. "They will not succeed," she said. At the informal foreign ministers' meeting in Wicklow she called the incident one with all the hallmarks of state-sponsored terrorism, and put the bloc's 22nd sanctions package, carrying roughly 1,600 listings connected to Russia's military-industrial complex, in the pipeline, EU Today reported. The Wicklow meeting cannot itself adopt sanctions.

On September 2, the European External Action Service called in Russia's ambassador in Brussels, France's Jean-Noel Barrot summoned the Russian charge d'affaires in Paris, and the Dutch and Belgian foreign ministers summoned Russia's ambassadors. Belgium's Maxime Prevot said the attack came in addition to a long series of unacceptable incursions on the territory of other EU and Nato allies in recent months. Poland, Italy, the United Kingdom, Sweden and the Czech Republic backed Germany's assessment. Those go back to the Polish drone incursion on September 10 when six Russian drones flew over most of Poland.

Russia's embassy in Berlin called the accusations absurd and warned of consequences, having earlier dismissed the affair as a fabricated provocation. Foreign ministry spokeswoman Maria Zakharova said Moscow would respond to Berlin's “anti-Russian” decisions.

Whether the promised response amounts to more than summonses is the open question. The EU's 21st package was watered down when member states pushed back on the oil price cap, and the largest instrument outside the bloc, the Lindsey O. Graham Sanctioning Russia Act, has also stalled in the US House with no vote scheduled after passing the Senate 86-11. A 22nd package of 1,600 listings would be the biggest yet, and it has to clear 27 capitals.

But there is a clear scaling up of the Russian threat that runs in parallel to the escalation in the tit for tat missile war in Ukraine. Drone incidents on Nato's eastern flank have been testing the alliance's defences for months, and Poland invoked Nato's Article 5 after Russian drones crossed into its airspace. Those were incursions into open sky. A device planted inside the fence of a working freight airport in the middle of Germany is a different proposition, and it is the one Berlin has decided to put a name to.