Newsroom September 23 11:56Tense scenes have prevailed since late Tuesday afternoon in central Oslo, where a powerful explosion occurred on Pilestredet Street, prompting a massive security response. After the first explosion, Norwegian police confirmed that additional unexploded devices had been found at the scene. Reports of an explosion having rocked Pilestredet in Downtown Oslo, Norway, possibly the result of a thrown hand-grenade. Police have cordoned off the area, with residents being told to stay away from the scene due to possible unexploded ordinance near Parkveien. Local media report that urgent warning messages were sent to residents’ mobile phones, instructing them to remain in safe places away from the explosion site.