Those hurt were taken to hospitals with most of the injuries ranging from cuts to broken bones. At least one person was in critical condition.
The storm slammed into the Cherrystone Family Camping & RV Resort shortly before 9 a.m. EDT Thursday. The sprawling campground on the Chesapeake Bay has pools, mini-golf, cabins and several piers for fishing. About 1,300 people were there when the storm hit, according to the state Emergency Management Department.
"All hell broke loose," said Joe Colony, who has been coming to the campground for 30 years. "We got an emergency message on a cellphone and within 30 seconds, the thing hit and it blew down 40, 50 trees in the park."
Virginia State Police spokeswoman Corinne Geller confirmed the deaths.
"It was a disaster. I don't ever want to do that again," said Colony, of Stephensville, Maryland.
The National Weather Service had issued a tornado warning for the area. A team was headed there to determine if a twister hit.
"It came in real quick," Eastville volunteer firefighter Brittney Eder told The Associated Press in a telephone interview. "The sky turned jet black."
Eder said she left the campground before the full force of the storm hit.
Joe Micucci said he and his wife couldn't escape in their car because of hail the size of softballs, so they rode out the storm in their camper. He said he felt fortunate they weren't hurt.
"We saw at least five (campers) that were flipped over. One was completely gone and only had its wheels left," said Micucci, of Washington Township, New Jersey.
Micucci and others were evacuated from the campground to a nearby high school. He said he wasn't sure when he would be able to go back and survey the damage.
The 50-year-old campground is located on 300 acres in rural Northampton County, according to its website.
Peter Glagola, spokesman for Riverside Shore Memorial Hospital, said the hospital was treating more than two dozen patients as of Thursday afternoon, most of which were in fair condition with injuries ranging from cuts to broken bones.
Glagola said more patients were expected to be brought to the hospital, which is about 30 minutes north of the campground. One patient in critical condition was flown to VCU Medical Center in Richmond, he said.
Hospitals in Virginia Beach and Norfolk had been preparing for mass casualties but had received just three patients, one of which was taken to a nearby children's hospital, said Sentara Healthcare spokesman Dale Gauding
Coast Guard spokesman Petty Officer 3rd Class David Weydert said crews also were responding to reports of boats overturned in the water in the area. Good Samaritans pulled at least three people from the water, he said, though their conditions were unknown.