AT&T said it had restored service to 96.5 percent of its cell sites in the impacted region as of Saturday morning and Verizon said its engineers were working 12-hour shifts to return service in the New York and New Jersey areas.

For consumers without service or without electricity, the major wireless carriers have established charging stations and are offering free telephone calls from several locations.

Most carriers are offering the service at their stores. Additionally, AT&T established such stations and T-Mobile said it is offering charging and calling service in American Red Cross shelters in the state of New Jersey.

Verizon said it is redirecting employees and resources to the New York and New Jersey area as it restores service in less-severely affected parts of the region.

"Fuel availability is a daily concern," Verizon said in a statement. "Verizon's command center continues to work with fuel suppliers and federal, state and local government officials to secure the fuel essential to keep generators and service vehicles running so Internet access and voice and data communications can continue to flow."