Power is out in portions of North Adams and Clarksburg as of late afternoon Sunday.

NORTH ADAMS — A total of 881 customers lost power Sunday at 3:31 p.m. in North Adams, Williamstown and Clarksburg.

An hour later, customers in the eastern portion of the area had regained power, with 595 customers still without electricity, 511 in North Adams and 84 in Clarksburg.

Just after 4:30, Christine Mulligan, spokesperson for National Grid, said the cause of the power failure had not been determined.

"We did some switching to bring as many customers back in the meantime," she said. "We'll update the estimated time of restoration when we find the cause."

Power was restored to the remaining customers at 6:06 p.m.

"It's likely vegetation on the wire," Mulligan said, meaning fallen tree limbs or vines.