The Johnson County Sheriff's Office is looking for two people who deliberately set 12 fires near Cleburne on Monday.
Investigators said two teenagers or men in their 20s set the fires in hopes they would become one big blaze.
But their plans were cut short by some quick-thinking electrical workers who just happened to be nearby.
"And as we were coming up we heard a mayday call," said Carlos Martinez, a lineman who works for United Cooperative Services.
He and three other workers overheard dispatchers deploying firefighters to a dozen different fires at about 5 p.m. and realized they were nearby.
"Well, we know it's pretty dry out," said Nick Taresh, a groundman who was with Martinez. "We don't want those fires spreading."
All the men grabbed the fire extinguishers that all their trucks are equipped with and put out four of the 12 fires.
"I believe we went through six and then we began picking up the shovels," Martinez said.
If all the fires had become one big blaze, it could have meant disaster for nearby homes, ranches and a state park, the Johnson County Sheriff's Office said.
The sheriff's office applauded the workers' quick thinking because their help allowed firefighters to battle other fires that were 2 to 3 acres in size before they could spread.
"It also gave the arson investigators more to work with instead of having water hoses push everything away," said Lt. Tim Jones, of the Johnson County Sheriff's Office. "It allowed them to have more of a crime scene to look at."
The workers said they were happy to help, saying it was easy for them because they are taught to do it as a part of their job.
"We are trained, like I said, as United employees, to assist in any way possible," Martinez said.
The Johnson County Sheriff's Office is also looking for a white Ford pickup.
Anyone with information is asked to call the sheriff's office at 817-556-6058.