ST. JOHNS COUNTY, Fla. -- Fire crews evacuate people from 15 homes and moved a few horses to safety Sunday when a brush fire near U.S. Highway 1 and state Road 206 grew from 20 to 300 acres in just a few hours.

"It got really black," Kurt Stoltman said. "The next thing I know ... this place was crawling with fire trucks, police cars, and paramedics."

SJC Fire-Rescue spokesman Jeremy Robshaw said some natural firebreaks in the area combined with some light rain overnight allowed crews to get a leg up on the fire. It was considered 100 percent contained Monday morning, although crews were continuing to watch hot spots to make sure the fire did not flare up again.

While no homes or structures were in immediate danger, dry conditions and winds averaging 15 mph prompted officials to move the people and some horses out as a precaution on Sunday afternoon.

"We watched it spread and spread and spread," Lola Stoltman told Channel 4's Jim Piggott. "When they told us to get out, we said 'We really want to stay,' and they said, 'No, you're going.'"

The American Red Cross opened a shelter at the Grace Point Church on U.S. 1, but only two families took advantage of it. Most stayed with friends until they got the all-clear to return to their homes.

Firefighters were still investigating what started the fire.