PORTLAND, Ore. (AP) — Members of the Oregon National Guard delivered supplies to people without power as problems lingered from an ice storm the wreaked havoc on the electrical grid, and a utility official said some communities may not see power for another week.

Almost 39,000 customers remained without power on Sunday, after Portland General Electric said it had restored power to more than 14,000 customers on Saturday. The utility said more than 400 crews were at work trying to restore power to remaining homes and businesses.

Guard members delivered emergency supplies including water and batteries to about 50 residents in Clackamas County, local authorities said.

The worst ice storms to hit the area in 40 years knocked out power to more than 420,000 customers and killed five people, including four who died from carbon monoxide poisoning as they tried to stay warm.

It could take as long as seven days to fully restore power, said Portland General Electric spokeswoman Elizabeth Lattanner. Some customers have experienced multiple outages, she said.

The damage and dangerous conditions left behind by the storm that started Feb. 12 were the worst in the utility’s history, according to officials.

“We would restore power in one area, move on to the next and then have to go back to that area because additional trees fell or something similar,” Lattanner said.

One-quarter of customers lost power multiple times over the course of the three-day storm as ice-laden trees fell on lines. A layer of ice an inch thick coated power lines and trees, adding 1,000 pounds of extra weight to each span of wire from pole to pole, PGE said.