Hawaii Electric Light Co. has significantly reduced the number of people without power in Puna, restoring electricity to about 2,500 customers Thursday.

About 3,800 people remain without power, down from 6,300 Thursday, company officials said Friday, a week after Tropical Storm Iselle slammed into the district.

Still, the company continues to warn residents that although crews are making progress, some areas may be without electric service for three weeks or longer depending on the extent of the damage.

The company said crews expect to continue making progress Friday in Nanawale Estates, Leilani Estates, Hawaiian Beaches, Hawaiian Paradise Park, and portions of Upper Puna.

HELCO has a customer information center at the Hawaiian Shores Community Center in Hawaiian Beaches where customers can ask questions and charge electrical devices. It is open daily from 8:30 a.m. to 4:30 p.m.