Residents walk along Highway 12, the main road that connects Cape Hatteras National Seashore to the mainland, after it was destroyed by Hurricane Irene in Rodanthe, North Carolina August 28, 2011. [Photo/Agencies]

WASHINGTON - Five million people in the United States are still without power as Hurricane Irene left a trail of destruction along the East Coast, federal officials said on Monday.

Craig Fugate, administrator of the Federal Emergency Management Agency, cited the figure from the Energy Department Monday in a White House briefing, saying it would take some time to restore power supply to all those affected.

After making its first landfall on Saturday, Hurricane Irene churned up north along the East Coast, killing at least 32. It has since weakened and entered Canada Sunday night, but many affected states are still facing the threat of flooding. Vermont and New Jersey are struggling with the worst flooding in decades.

"It's going to take time to recover from a storm of this magnitude," President Barack Obama said earlier Monday.