CHESAPEAKE, Va. (WVEC/AP) -- Virginia officials are reporting one storm-related death after Hurricane Matthew. That brings the overall U.S. death toll from the storm to at least 21.

Officials in Virginia say the driver of a pickup truck was killed when the truck rear-ended a tractor trailer stopped for a downed tree on Interstate 64, east of Military Highway in Chesapeake on Saturday.

The pickup truck's driver, 38-year-old Anthony Longoria, was taken to the hospital, where he later died. State Police say Longoria was not wearing his seatbelt at the time of the crash

Virginia Department of Emergency Management spokeswoman Dawn Brantley said Monday that the death was storm-related. She says officials haven't yet determined whether the death of a man found in standing water in Hampton is storm-related.

State Police also say they are investigating a single-vehicle fatality in Isle of Wight County, although it's not clear if that crash is storm-related.

Investigators say a Lexus driven by 36-year-old Linwood Morris Barnes of Hampton was traveling south on Route 709 when the car went off the road, striking a culvert which overturned the vehicle and sent it into an embankment. Police say Barnes was also not wearing his seatbelt at the time of the crash.

Dominion Virginia Power says nearly 100,000 customers in Virginia are in the dark Monday, most of them in southeastern Virginia.

Hampton, Newport News, Suffolk, Norfolk, Portsmouth, Virginia Beach and Middlesex County have declared states of emergency.

The other deaths occurred in North Carolina, with 10; Florida, four; South Carolina, three; and Georgia, three.