SPRINGFIELD, Mo. (AP) – A small plane crashed early Saturday in southwest Missouri, killing the pilot, his three children and a businesswoman.

Missouri State Highway Patrol spokesman Jason Pace said the single-engine plane went down about 12:30 a.m. northwest of the town of Willard, leaving all five people on board dead. The 2002 Cirrus SR22 appeared to have been headed toward the Springfield airport when it crashed about five miles away.

“The plane totally disintegrated after the crash,” said Pace, who had been to the site. “It burned, just into pieces. It was a very tragic and horrific site.”

Troopers were securing the scene and waiting for investigators from the National Transportation Safety Board and the Federal Aviation Administration to arrive.

Keith Holloway, a spokesman for the NTSB, said he couldn’t provide any details about the investigation, but that the agency’s preliminary report may be available within two weeks. The FAA didn’t immediately return a phone call for comment.

Pace identified those killed as Robin Melton, 46, of Ozark, and John Lambert, 44, and his children, Joshua Lambert, 10, McKinley Lambert, 15, and Grayson Lambert, 16, all of Springfield.

Pace didn’t know the relationship between Melton and Lambert. He said John Lambert was the plane’s pilot.

“This accident is a real tragedy. The number of people affected is in the thousands,” David Cheek, who coached Grayson Lambert at Lake Country Soccer for six years, told the Springfield News-Leader.

The newspaper reported that Melton owned an environmental consulting firm called Environmental Works Inc., and Lambert owned Missouri Insulation & Supply Inc.

Melton also served on the board of the Springfield Chamber of Commerce and the Watershed Committee of the Ozarks. Lambert, a former Drury University swimmer, was picked in June to serve as chairman of the Board of Directors of the OTC Foundation, the fundraising arm of Ozarks Technical Community College.

OTC Chancellor and President Hal Higdon told the News-Leader that Lambert “was not a loud or boastful person” but was passionate about his work. He said Lambert also was “crazy” about his three kids.

Pace said investigators are looking into reports that the plane had taken off from the Kansas City suburb of Lee’s Summit. He said he couldn’t comment on what led to the crash.

David and Krista Guy of Walnut Grove told the News-Leader that they heard what sounded like the plane’s engine cutting in and out before the crash.

“The house shook,” Krista Guy said. “It was just unbelievable.”

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