(CNN) -- Some of the largest wildfires in Texas were almost completely contained, but weather conditions posed risks for fires to spread, the Texas Forest Service said Wednesday.
Thousands of local firefighters and more than 200 state agents were battling fires in a large swath of the state. In the past week, the Texas Forest Service has responded to 76 fires that burned 131,237 acres. Most of the fires were across the Texas Panhandle.
As of Wednesday, three of the biggest fires were still active, but were largely contained, the forest service reported. One of the biggest was in Potter County, where more than 24,000 acres burned. A 13,700-acre fire in Mitchell County was 80% contained.
Three new fires were reported, including a troublesome one covering 1,100 acres below Alpine in Brewster County, according to forest service spokesman Lewis Kearney.
Officials have urged residents to be cautious in their outdoor activities, but some of the blazes seemed almost unavoidable.
The muffler of a truck stuck in the sand in Howard County ignited a grass fire Wednesday morning. The driver was able to get out of the vehicle, but the truck was destroyed, reported CNN Odessa affiliate KWES. The 350-acre fire was contained by mid-afternoon Wednesday.
High temperatures and humidity below 10 percent in some areas posed a fire danger, the agency said.
Southeast Texas became very active on Tuesday, reporting 13 fires burning 288 acres, the service said.
At least 78 houses have been consumed by the fires, which at their peak were burning the length of a football field every minute.
On Tuesday, Mark Stanford, chief of fire operations for the forest service said officials were pushing to contain fires by Thursday because the weather outlook indicated "Friday will be another bad day for us."
"It will be a very high fire danger day across that region," he said. "So we want to make sure that we've freed up all of our fire resources so that they can respond to new starts we may have."
Smoke from one fire caused an accident that killed a 5-year-old child Sunday on Interstate 20.
Officials believe many of the fires were started by power lines that fell from high winds. Officials are urging citizens to be very cautious with their outdoor activities on fire danger days.
One fire was caused by an individual grinding on metal pipe, Stanford said. A blaze in Midland was caused when a vehicle tire blew and the tire rim created sparks.
The fires occurred in an area of about 45,000 square miles, the size of Kentucky, Stanford said.
CNN's Dave Alsup, Mariano Castillo, Phil Gast and Antoinette Campbell contributed to this report.