Joe Caffrey/KSTP-TV via A
This Monday, July 27, 2015 photo from video provided by KSTP-TV shows authorities at the scene of a plane crash near Amery, Wis. Police say four people died when the single-engine Beechcraft crashed and caught fire. Several hours later in Minnesota, a fixed-wing plane carrying three people crashed in a cornfield near Pipestone killing all aboard, authorities said Tuesday.

Two small planes crashed within hours of one another in western Wisconsin and southwestern Minnesota, killing all seven people who were onboard the aircrafts, authorities said Tuesday.

Four people died when a single-engine Beechcraft crashed and caught fire in a field near Amery, Wisconsin, about 50 miles northeast of Minneapolis, at about 5:30 p.m. Monday, Polk County sheriff's officials said. Firefighters extinguished the blaze, which scorched the surrounding field, and found the victims inside.

Karen Olson said the plane crashed on her property about 200 yards from her home.

"I thought it was a helicopter flying overhead," Olson said. Her property is in the flight path for medical helicopters flying to the nearby Amery Regional Medical Center, she explained. Then she heard her neighbor pounding on her door.

"He just said, there's an airplane that went down in your field and the field is on fire," Olson said. "All I could see was smoke."

The Midwest Medical Examiner's Office in Anoka, Minnesota, will conduct autopsies and identity the victims.

Several hours later in Minnesota, a fixed-wing plane carrying three people crashed in a cornfield near Pipestone, authorities said Tuesday. The pilot and two passengers were pronounced dead at the scene, according to the Pipestone County Sheriff's Department.

Travis Jasper said he and his construction crew were just finishing work for the day near the crash site when he heard what sounded like a plane in trouble.

"(I) heard it spitting and sputtering. It fired up a couple times and then I thought I heard a car door slam." Jasper told KSFY-TV. "A couple minutes later I seen the neighbor at the corner and he's like, I think a plane just went down, and I said yah, I think the same thing."

Jasper said he and his crew jumped on top of their vehicle to try to spot the plane in the cornfield.

Authorities haven't identified the people involved in either crash or their departure or destination locations.

The Federal Aviation Administration and the National Transportation Safety Board have launched investigations.

"We'll document the scene, examine the wreckage of the aircraft and later move it to a secure facility," NTSB spokesman Keith Holloway said of the Wisconsin crash.