OKLAHOMA CITY — Wildfires fueled by extremely dry conditions and strong winds destroyed dozens of homes in Oklahoma City and North Texas on Tuesday and forced hundreds of residents to evacuate.

Officials did not yet know what started the blazes, but a summer heat wave and drought in Oklahoma and Texas have left the ground parched and vegetation dry.

“We’re in severe drought conditions, so just the tiniest little spark can start a wildfire,” Texas Forest Service spokeswoman April Saginor said.

In Oklahoma City, bursts of flame rose amid thick black smoke as oil-packed cedar trees ignited, giving gawkers a stunning view even from blocks away. Utility poles lit up like matchsticks, and power was out to more than 7,000 homes and businesses.

The fire destroyed 10 to 12 homes and consumed 1,500 acres in a sparsely populated and heavily wooded section of the city, fire department spokesman Mark Woodard said. Several hundred homes were evacuated, according to Red Cross spokesman Rust Surette.

Meanwhile, a fast-moving wildfire in North Texas destroyed at least 20 homes and prompted authorities to evacuate at least 125 other homes in a lakeside community, state Forest Service officials said.

Agency spokesman John Nichols said the fire, which started earlier in the day, had spread to about 7,500 acres in Palo Pinto County by Tuesday night. Part of a state highway was shut down in the area because of tall flames and huge plumes of smoke, officials said.

Temperatures in the area got up to 106 degrees on Tuesday afternoon with winds gusting up to 28 mph, said National Weather Service meteorologist Jason Dunn. He said by nightfall, gusts were at about 20 mph and the temperature was around 99.

The Oklahoma City fire was largely under control by Tuesday night, but a flare-up at the head of the blaze was in a wooded area that firefighters were having trouble reaching, Woodard said.

“Luckily the sun is going down and everything will calm down,” Emergency Medical Services Authority spokeswoman Lara O’Leary said Tuesday evening. “It’s been a long day.”

O’Leary said four people, including two firefighters, were treated for minor injuries. Three were transported to hospitals where all were in good condition, she said. No major injuries were reported in Texas.

Air tankers and helicopters were brought in to help fight the blazes.

The fire in Oklahoma City’s rural northeast corner paralleled Interstate 35, with smoke rolling northward as strong winds stoked the fire. From time to time flames could be seen amid the roiling black cloud. The blaze moved about four miles from where it started about 1 p.m., Bryant said.

“This is a heavily wooded area,” Bryant said. “There are cedar trees out here. Cedar trees burn very hot. They’re very heavily laden with oil. A lot of times when the cedar trees do go up, they burn very hot.”

A separate grass fire was reported near Bethel Acres, just east of the Oklahoma City area, said Jennifer Dawson at the Pottawatomie County Emergency Management.