1:30 p.m.
One person is unaccounted for this afternoon after a 2-alarm fire ripped through a Woodbridge townhome early this morning.
Investigators from the Prince William County Fire Marshal’s Office, ATF, and county police were on the scene of the blaze just after noon today. Investigators are unable to enter the house.
“There is heavy fire damage to the house… the rear of the home is bowing, and it might collapse,” said Prince William fire and rescue spokesman Tom Jarman.

Fire crews will bring in a crane to help stablize the home. Crews will treat the operation as they do any other “structure collapse” often seen when a vehicle slams into the house.
The county’s fire department is the lead investigating agency for this incident right now. It has not put out a description of the person who is said to be unaccounted for.

A police crime scene truck left the scene about 12:30 p.m. That agency may be called to investigate once it is safe enough for emergency crews to enter the house, said Prince William police spokesman Nathaniel Probus.
Original post
Fire investigators are now looking into what caused an early-morning blaze on Ponderosa Court in Woodbridge.
More in a press release:

Woodbridge, VA March 16, 2016 2:42 a.m. – Occoquan-Woodbridge-Lorton Volunteer Firefighters responded to the report of a townhouse fire at 14635 Ponderosa Ct in Woodbridge. When crews arrived, the townhouse was heavily involved in fire. A second alarm was immediately requested and dispatched.
Having information that someone might be inside, first arriving crews attempted entry from the front of the townhouse, however conditions were not stable and crews were forced to exit the building. Fire was under control within an hour. Due to significant damage and a structural collapse potential, crews are still not able to enter the townhouse and remain on the scene waiting non fire department construction assistance.
The blaze is under investigation by the Prince William County Fire Marshal’s Office. American Red Cross was called to assist neighboring families with temporary housing. Fire and Rescue units from OWL VFD, Dale City VFD, Dumfries-Triangle VFD, Fairfax, PWCDF&R, and PWCPD responded to the incident.
More as we have it.