New Castle, Colo. ? White and yellow smoke billowed into the western Colorado sky Tuesday as firefighters battled three wildfires likely sparked by lightning that have burned more than 1,800 acres and forced evacuations of 90 homes.

One fire was burning in steep terrain dotted with rural subdivisions between New Castle and Glenwood Springs, about 160 miles west of Denver. The blaze had grown to 800 acres, or just over a square mile.

No structures had burned, but one firefighter suffered a hand injury, said Suzanne Silverthorn, a spokeswoman for fire commanders.

Residents of 110 more houses were advised to leave. It was not immediately known how many people had left their homes. Three people had checked in to a school being used as an emergency shelter in New Castle.

“It’s been a really scary fire,” Garfield County Sheriff Lou Vallario said. “Its behavior has been bizarre. We’re struggling to get a handle on it.”

Bureau of Land Management spokesman David Boyd said the fire was moving east, toward the homes. On Monday, firefighters said the flames were within a half-mile of houses, but Boyd had no new distance on Tuesday.

A second fire in a remote and rugged area near the town of Cameo, 180 miles west of Denver, had reached 1,000 acres by Tuesday morning but had not grown further by mid-afternoon, BLM spokeswoman Mel Lloyd said. Three aircraft and 75 ground crew members were on scene.

One fire near Parachute had been held to just 4 acres but was a concern because it was just 200 yards from homes and natural gas wells.

All three fires were blamed on lightning strikes Sunday.