CARIBOU — Emera Maine says more than 1,800 customers are without electricity in northern Maine because of an outage of unknown origin.

A spokesman for the utility says crews are inspecting a transmission line on Thursday to determine the cause of the outage. It is affecting customers in the Caribou, New Sweden and Woodland areas and other nearby communities. The spokesman says crews hope to isolate the problem and restore service before noon on Thursday.

The utility says the outage is affecting 1,872 customers in Aroostook County and one in Washington County. The spokesman reminds customers using alternate heating and power sources to exercise caution.