A suspect has been arrested after emergency services rushed to the centre of Oslo following reports of an explosion. A second device found at the site appeared to be a "military-style" hand grenade, officer Brian Skotnes revealed. Officers had told residents in the nearby area to stay away from their windows, however, Mr Skotnes said "the area was now safe". "Given that there is still an explosive device in the area, the police wish that people stay away from windows." In a statement, the force added: "Residents in the area are asked to stay away from windows.