Germany has accused three men of plotting to use exploding packages to commit arson attacks, apparently on behalf of the Russian state, marking the latest alleged case of hybrid warfare being waged by Moscow on European soil.

The suspects, two men and one woman, were detained in separate operations in the western city of Cologne, the southern city of Konstanz and in Switzerland. All three are Ukrainian nationals and are being held on suspicion of espionage and preparing acts of sabotage.