Sweden's security services are investigating three incidents involving unidentified drones above its Frosmarks, Oskarshamn, and Ringhals nuclear power plants last Friday. Sweden's military, last week, also reinforced patrols on and around its Baltic Sea island of Gotland amid a dramatic spike in Nato-Russia tensions. "Security threats against Sweden have increased with a ... more complex threat picture," the security service said in a statement on Monday.
