Baku, December 23, AZERTAC Police have launched an investigation after a powerful blast at a popular Stockholm restaurant just a week before it is set to open its doors to revellers for its annual New Year's Eve celebrations, according to The Local. A police bomb squad was called to examine the scene at Berns salonger in central Stockholm at 4.19am on Wednesday after an “explosive object” was thrown at the restaurant. The normally busy social hub was closed to customers at the time, but staff were inside. However no one was believed to have been injured in the blast. It is the second violent incident at a nightclub in the Swedish capital in recent weeks. On December 8th police launched a probe after a man fired a series of shots at Sturecompagniet in the busy Stureplan square.