A power line problem might have caused a fire last week that destroyed Shuri Castle, a symbol of Okinawa located at a World Heritage site, police sources said Tuesday.A surveillance camera captured flashing light at the left backside of the burned-down Seiden main building of the castle's first floor shortly before and after the fire started at around 2:34 a.m. on Thursday, separate sources familiar with the situation said.When the fire broke out, a thermo-sensitive sensor at the building activated, and the police sources said other security camera footage showing a flame flaring up on the …READ FULL ARTICLE