More than 450,000 households in Maryland remained without power 35 hours after peak rain and winds from Hurricane Irene hit the state, and the Baltimore area could experience outages until Friday, officials said Monday.

“We have not stopped working since the storm hit,” Gov. Martin O'Malley said from the Maryland Emergency Management Agency’s Reisterstown headquarters. But many remained in the dark.

"There are some people who are going to be without electricity for a long period of time—several days,” he said. “We will try our best to give you better estimates so you can make accommodations.”

Peak power outages hit Sunday, with 822,000 homes' electricity knocked out by winds of up to 65 mph and heavy rain. Wind gusts peaked at 85 mph.

BGE, which covers Baltimore County, Baltimore City and seven surrounding counties, had by far the most without power—354,000—while SMECO, which covers southern Maryland, had 43,000, and Pepco had 40,000, most of which were in Prince George's County. Delmarva had 31,000 customers in the dark, Choptank Electric 3,000 and Allegheny Power had 59, according to O'Malley.

BGE spokesperson Linda Foy said full power is expected to be restored by late Friday. She said getting traffic lights back online was a top priority.

BGE has 2,000 transformers out, which will be repaired after the company fixes its transmission lines, substations and feeders, O’Malley said.

MEMA director Richard Muth said crews clearing roads are concentrating on main thoroughfares and making sure roads to critical infrastructure such as hospitals are clear. MEMA is teaming up with recovery crews to get poles and wires back up as well, he said.

“They’re going non-stop with it,” he said.

The Eastern Shore, which the governor said was hit hardest by the storm, has made some of the best progress in power restoration, O'Malley said.