A state senator from North Dakota, his wife and two of their children were killed on Sunday evening when a small plane he was piloting crashed at an airport in Moab, Utah, the authorities said.
The senator, Doug Larsen, 47, a Republican, was flying the single-engine plane when it crashed right after taking off from the Canyonlands Regional Airport, over 200 miles southeast of Salt Lake City, according to the Grand County Sheriff’s Office.
The authorities were notified of the crash at 8:26 p.m., and sent emergency responders, the Moab Valley Fire Department as well as other airport and medical staff, the Sheriff’s Office said in a statement posted to Facebook, noting that all four people, including Mr. Larsen’s wife, Amy Larsen, had died.
The cause of the crash remains under investigation.
The authorities said at a news conference on Monday afternoon that they were looking into Mr. Larsen’s history as a pilot, as well as the maintenance of the aircraft and the weather conditions.
Public records show that Mr. Larsen was last registered in June to fly the single-engine plane, a Piper Cherokee PA-28-140.
In an email to fellow senators, Republican Senator David Hogue, the majority leader, said that Mr. Larsen and his family had been returning home after visiting family in Scottsdale, Ariz., and had stopped to refuel in Utah, The Associated Press reported.
“I’m not sure where the bereavement starts with such a tragedy, but I think it starts with prayers for the grandparents, surviving stepchild of Senator Larsen, and extended family of Doug and Amy,” Mr. Hogue wrote. “Hold your family close today.”
Mr. Hogue confirmed by email on Monday afternoon that he had sent the letter, but did not immediately provide any additional comment.