Security at Sweden’s power stations has been increased following the discovery of suspected explosives at Ringhals nuclear plant.

The package was found during a vehicle check at the plant, which has four reactors and produces 20 per cent of Sweden’s energy.

The plant is 70 per cent owned by Vattenfall, which said in a statement: “A suspected explosive was discovered in a truck on its way in to Ringhals’ operating facility. A sample of the material was sent to the Swedish National Laboratory of Forensic Science for analysis.”