SYDNEY: A powerful 7.5-magnitude earthquake struck Papua New Guinea on Monday, with unconfirmed reports of blackouts and damage to buildings, officials said. The quake’s epicenter was around 90 kilometers (55 miles) south of Porgera in Enga province, according to the US Geological Survey, and hit at a depth of 35 kilometers. The quake hit PNG’s mountainous interior and US scientists said there was no tsunami threat. Social media posts reported blackouts and damage to buildings at Porgera. The quake’s epicenter is in rugged terrain about 612 kilometers northwest of Port Moresby.