(CNN) -- Investigators are trying to determine what caused a fiery plane crash in a Utah neighborhood, while the aircraft's pilot remains in critical condition, authorities said.
The Cessna 210 single-engine plane, which ripped into pieces as it plunged to the ground, went down shortly before 6 p.m. Sunday in a residential area of Roy, Utah, according to Ogden police dispatcher Brittany Dean.
Pilot Clayton Roop, 46, survived the crash and was in critical but stable condition at the University of Utah Hospital, Roy Police Chief Greg Whinham said Sunday.
The plane had been cleared for landing at nearby Ogden Airport when it crashed, said Mike Fergus of the Federal Aviation Administration.
Gary Cox was in the neighborhood, attending a family birthday party, when the power went out right after the plane went down. He told CNN affiliate KSL that he and a few other people found Roop lying on the ground.
"He was confused, hurt and in a lot of pain," Cox said. "But he was able to answer questions and get where he needed to be."
The plane's engine sat in the front yard of a house, Cox said, with other parts strewn throughout the neighborhood.
Two occupied homes -- one with three people inside, the other with two -- caught fire after the crash, Roy Fire Department Chief John Ritchie told KSL. But no one inside was hurt and, within about an hour, firefighters extinguished the flames.
The crash knocked out power for 1,700 homes, starting at 5:58 p.m., said Margaret Oler of Rocky Mountain Power. By 7:10 p.m., power had been restored to all but 875 customers. A nearby elementary school was opened as a temporary shelter for those without heat and lights, Ritchie said.
Visibility was minimal at the time of the crash, as the National Weather Service had issued a dense fog advisory for the area. That warning remains in effect until 9 a.m. Monday.
The FAA is investigating the crash, along with Roy fire and police officials.
Roy is about 6 miles southwest of Ogden, with the affected neighborhood near Ogden-Hinckley Airport.
CNN's Greg Morrison, Leslie Tripp and Amanda Watts contributed to this report.