A sign in Moyock, N.C., warns travelers that access to both Hatteras and Ocracoke Islands is restricted to residents only on Saturday. (Steve Earley/AP)

A steady stream of tourists left a North Carolina island Saturday under evacuation orders prompted by a widespread power outage, wiping out a significant chunk of the lucrative summer months for local businesses.

It could take days or weeks to repair an underground transmission line damaged early Thursday by construction crews working on a new bridge between islands in North Carolina’s Outer Banks. The construction company drove a steel casing into the line, causing blackouts on Ocracoke and Hatteras islands.

Cars lined up Friday to get on ferries, the only way off Ocracoke Island, after about 10,000 tourists were ordered Thursday evening to evacuate. A second order for visitors on Hatteras Island, south of Oregon Inlet, meant up to 60,000 additional people had to evacuate starting Saturday, primarily north over the inlet bridge.

As of Saturday afternoon, ferries had evacuated about 3,800 people and 1,500 cars from both islands, according to Gov. Roy Cooper’s office.

Cooper (D) said he called local officials to pledge state help. “We’ll do all we can to get repairs moving,” he said in a news release.

Customers enter the darkened Island Convenience Store in Rodanthe on Hatteras Island, N.C. (Steve Earley/AP)

Excavation revealed Saturday that one of three underground transmission cables that supply the islands’ power is missing a two-foot section. A timetable for repairs won’t be known until crews determine whether either of the other cables was damaged, according to the Cape Hatteras Electric Cooperative.

Dare County spokeswoman Dorothy Hester had no estimate for how many people had yet to leave Hatteras Island.

“We realize people are disappointed. They brought a lot of stuff here. They’re packing up and moving out,” she said.

Roughly 80 percent of the islands’ tourism stems from vacation rentals, and the order coincides with the customary Saturday turnover for weekly home rentals. The big question is when visitors can get to homes already rented for upcoming weeks, said Lee Nettles, director of the Outer Banks Visitors Bureau.

The order barring inbound tourists did not apply to Hatteras Island’s roughly 6,000 year-round residents or other property owners.

The island’s regular summer fish fry went on Saturday evening because organizers ordered the fish before the evacuation call.

The utility is supplying temporary power to residents, businesses and emergency services with diesel and portable generators.

Aaron Howe cooks in the dark kitchen at the Island Convenience Store in Rodanthe on Hatteras Island, N.C.. (Steve Earley/AP)