MCROSS -- The Greenbrier County Sheriff's Department said Terry Patterson, Jr., Kelly Wickline, Tiffany Williams and Tara Patterson are in critical but stable condition at the University of Virginia Medical Center.

Terry Patterson Sr. was treated and released from Greenbrier Valley Medical Center. Tacy Patterson is in critical condition at Charleston Area Medical Center.

All six range in age from 18 to 54 years old.

"All patients that were shipped out of Greenbrier Valley was also deconned prior to leaving the hospital for transport to the trauma facilities," said Gary Workman with the Greenbrier County Sheriff's Department.

Deputies said one deputy and three paramedics were decontaminated Monday as well. The patients' clothing is being sent to the state crime lab for analysis.

At this point, investigators said they are not sure what caused the powerful blast that destroyed the Patterson family home in McRoss. They said aerial photos confirm the home's propane gas tank was not damaged in the explosion.

The house blew up then caught on fire just before 7 a.m. Monday morning, Nov 23.

"I thought somebody had blown the side off my house out," said Rhonda Berry, who lives nearby. "I mean it was that, and it shook and rattled and knocked what-nots off the wall."

The home is located between Charmco and Rainelle.

The State Fire Marshal's Office and the Greenbrier County Sheriff's Department are investigating.