This story was updated at 5:45 p.m. April 3, 2012.

A 74-year-old Fort Washington woman was killed Tuesday morning after driving her Jaguar into a wooded area off the Capital Beltway’s outer loop just before Branch Avenue, a Prince George’s fire official said.

Around 9:30 a.m., Una Hightower Flack drove the 2002 sedan off of the right side of Interstate 495 near Camp Springs and into several trees, where the vehicle was found upside down with her inside, said Mark Brady, chief spokesman for the Prince George’s County Fire/EMS Department.

Maryland State Police are investigating the incident. Cpl. Yolanda Stockton, an MSP spokeswoman, said the cause of the crash has not been determined.

“She just drove her vehicle off the roadway and struck a tree,” she said. “We don’t know if she had a medical issue.”

A home phone number for Flack’s family could not be located.

djgross@gazette.net