More than 50,000 customers across the state, some of them in Concord, lost power yesterday as gusting winds knocked trees into power lines, sending utility companies scrambling to make repairs.

It could take days for some customers to see power restored, according to utility spokespeople.

As of last night, Public Service of New Hampshire reported 11,000 outages, down from 42,000 earlier in the day. Unitil reported 693 outages in the Concord area, down from 744 in the afternoon.

But while the overall numbers dropped throughout the day as homes regained power, new outages cropped up due to ongoing winds, which reportedly topped 45 mph.

"What's been happening with the winds, you stay on top of the outages, but they're scattered, and they continue," said Unitil spokeswoman Stephanye Schuyler.

She said the company - which yesterday evening still had outages in Concord, Epsom, Bow, Canterbury, Chichester, Salisbury and Webster - hoped to have power restored everywhere last night or early this morning.

Residents in Tilton and Hillsboro were among the tens of thousands of PSNH customers who lost power yesterday. With 90 line crews at work last night, PSNH spokesman Matt Chagnon said it could take days for the utility's customers to see their power restored.

"We're hoping that once the winds begin to die down . . . that we sort of have a better idea where we are with outages," Chagnon said early yesterday evening. "They're definitely scattered around the state."

The winds kept firefighters busy yesterday, with crews spending much of the day responding to reports of downed power lines - "dozens, probably," said Concord Battalion Chief Bill Weinhold. "The power companies are just so overwhelmed at the moment."

Crews are putting down caution tape in some places, Weinhold said, but until the power companies come through, "we just ask people not to go near them if they see them in the road," he said.

PSNH opened its emergency operations center in Manchester yesterday and has requested additional line crews from out of state, Chagnon said. Though winds were to blame for the majority of outages, Chagnon said some of the company's customers in the northern part of the state lost power after a foot of wet snow fell Friday evening.

More than 10,000 New Hampshire Electric Coop customers, including residents in Alton and Gilmanton, also lost power yesterday. National Grid reported scattered outages as well.

The Associated Press contributed to this report.