The eastern section of the island was plunged into darkness for several hours on Wednesday night following a system failure at the Jamaica Public Service Company (JPS).
Sections of other parishes also experienced power outages.
A JPS Spokeswoman told our news centre that all of Portland and St. Thomas were left without electricity for nearly two hours due to a shortfall in generation capacity.
RJR News was told that the unexpected load shedding exercise that began at about 6:30 pm affected households and businesses in St. James, Haover, St. Elizabeth, Westmoreland, St. Andrew, St. Thomas and eastern Portland.
According to the Port Antonio Police emergency procedures had to be put in place to deal with the outage and these remained in place until the lights returned at about 8 pm.