An explosion at Platinum Printing in Phoenix, Arizona last Thursday blew off the roof and seriously injured the four men who were inside the shop, the Associated Press reports.
The cause of the explosion remains under investigation, but the ATF is looking at the possibility of a fuel-air explosion resulting from the ignition of a gas leak.
Two brothers who own the shop were injured in the blast, as well as two other men.
A doctor from the Arizona Burn Center in Phoenix told the AP that two of the men were in critical condition, and the other two were in serious condition. All four will need surgery, and all are expected to recover.
“It was a pretty devastating explosion,” Chandler Fire Battalion Chief Keith Welch told reporters. “The inside of the building is completely destroyed, and if you get closer to the building, the walls have been pushed out.”
Read more at the Associated Press.