Washington (AFP) – Most people in Puerto Rico woke up Thursday with no electricity after a blackout hit the entire US island territory in the Caribbean. The Luma electric company said the outage Wednesday evening may have been caused by a failed circuit breaker at a power plant. It said the precise cause was not yet known. The specialized website poweroutage.us said that as of 0320 GMT Thursday, all 3.2 million residents of the island were without electricity. “Given the massive size and scope of the outage, power restoration could extend well into Thursday and Friday for some areas,” Luna sai…