Power company crews were making progress in turning the lights back on Wednesday for thousands of customers who were blacked out in the Dakotas by this week's blizzard, and most highways had been reopened.

Utilities faced staggering damage from the ice and snow that the storm plastered onto power lines and poles.

"There are places where there are miles of poles down," said Otter Tail Power Co. spokeswoman Cris Kling.

Otter Tail still had about 5,000 customers without power in the Dakotas and Minnesota on Wednesday morning, down from an earlier figure of 18,000, which "was probably a low estimate," Kling said.

In South Dakota, about 29,000 customers in 77 cities and towns plus some rural areas remained without power or had only intermittent power Wednesday morning, Gov. Mike Rounds said. That was down from about 50,000.

Rounds said the blizzard brought down about 8,000 utility poles and 10,000 miles of transmission line in his state. In some of the hardest- hit areas, power may not be restored for five to 10 days, the South Dakota Rural Electric Association said.

North Dakota National Guard officials said they provided five small generators to the town of Fairmount, which was without power, and another generator to run water pumps in Hankinson.

Temperatures fell into the single digits during the night in eastern North Dakota, with a low of just 3 above zero at Wahpeton, the National Weather Service said.

The Minnesota National Guard had provided a large generator to supply limited heat and light for the west-central Minnesota town of Wolverton, where about 20 residents spent Tuesday night and early Wednesday in the fire hall-community center.

"Nobody's worried about what's going to happen any more. We're just waiting for a nice warm shower and some heat," said Wolverton Mayor Jodi Tracy.

Dakota Valley Electric Cooperative, which serves some 5,000 mostly rural customers in southeastern North Dakota, was among the hardest hit by the blizzard that struck on Monday, said operations manager Craig Rysavy.

"I've been here 25 years and I've never seen anything like this — not even close," Rysavy said. "We're looking at extensive restoration. We'll probably spend a year getting back the way it should be."

The North Dakota Highway Patrol had reopened sections of Interstates 94 and 29 that were closed because of poor visibility and slippery pavement during the storm.

Snowplows had reopened all two-lane and interstate highways in South Dakota, officials said. Crews had to clear about 400 miles on I-90 and I-29 and more than 6,000 miles of other state roads.

Storm-closed sections of interstates across sections of Nebraska, Kansas and eastern Colorado had been reopened earlier.

At least five deaths were blamed on slippery roads in Minnesota, South Dakota, Nebraska and Kansas. A sixth person was killed by a tornado spun off by the big storm system in Arkansas.