Grass fires driven by gusty wind damaged several homes in Oklahoma and threatened others in north Texas on Tuesday. Three Oklahomans suffered minor injuries, authorities said.

The biggest fire burned at least 400 acres in a rural area near the town of Mustang, southwest of Oklahoma City.

TV station helicopter footage showed at least a half-dozen structures were burned in Mustang, but conditions appeared to improve by late afternoon, when fire crews brought the flames under control.

"We've still got some hot spots that we're concerned about," Mustang Police Chief Monte James said.

He said firefighters battled flames at four houses and sheds. One firefighter was being treated at a hospital for smoke inhalation.

After the flames passed, residents emerged and were "watering their yards and standing in their yards," said Harold Percival, who lives about a mile from the Mustang fire.

"What can you do about it," Pat Hankins, 62, said as he watched his one-story home burn. "You have no control."

Hankins' friend Maria Vantour-Smith said flames hopscotched around Hankins' property before reaching his home.

"It just kept jumping. I've never seen anything like it," she said. They were able to remove a few antiques and other items from the home before it was gutted.

Several other grass fires were brought under control in three areas of Oklahoma City. One firefighter suffered heat exhaustion, and a child suffered minor burns on his hands when a shed caught fire.

That blaze was apparently started by children playing with fireworks, Oklahoma City Fire Maj. Brian Stanaland said.

The cause of the Oklahoma blazes was under investigation, but officials said sparks from power lines were one possibility.

Smoke from other grass fires reduced visibility along Interstate 35, forcing officials to close a stretch of the highway in southern Oklahoma near the Texas line.

The wind in Oklahoma was clocked at 25 to 35 mph, with gusts as high as 40 mph.

In Texas, Gov. Rick Perry said dozens of fires, mostly in north and central parts of the state, prompted him to deploy firefighters and issue a disaster declaration.

"We are working hard from both the ground and the air to protect Texans and their homes and property," Perry said in a statement.

Fort Worth Fire Department Lt. Kent Worley said crews had fought nine brush fires during the first half of the day and he expected more. His department also helped battle a blaze in nearby Kennedale. The Dallas Morning News reported that flames in Kennedale threatened two apartment complexes.

In Arlington, fires threatened new housing developments and apartments.

"It's like trying to stop a 30-mph car coming down the street," Deputy Fire Marshal Keith Ebel said. "The wind is the worst enemy right now."

In Hood County, a fire near Canyon Creek forced at least 100 people to evacuate, said Chief Deputy Jerry Lind. He said several structures were on fire, and propane tanks had exploded.

"We've got fires burning structures in several counties," said Tracy Weaver of the Texas Forest Service. "It is just critically, critically dry out there right now."

There were no immediate reports of injuries in Texas.