An investigation is underway after an aircraft contracted by the Minnesota Department of Natural Resources crashed into a rural Remer lake on Tuesday afternoon, leaving the pilot with minor injuries.

According to the Cass County Sheriff’s Office, the crash was called in just after 2 p.m., with witnesses saying the plane had entered the southern end of Inguadona Lake in Trelipe Township.

The pilot, identified as a 56-year-old Texas man, was rescued by witnesses to the crash. Authorities add he was treated at the scene for his injuries, and didn’t need any further assistance.

5 EYEWITNESS NEWS spoke to two friends from the metro area who were out on a fishing trip up north when they heard the crash.

Vern Wagner and Jeffrey Nelson were out fishing on Inguadona Lake on Tuesday afternoon when they saw a “huge splash.”

“[We] reeled up real quick, got the motor going, and roared up to that end of the lake,” said Wagner. “You could see where it was because [it was] boiling up from the bottom, was air bubbles and the smell of gasoline.”

The Cass County Sheriff’s Office says the plane, an air-tractor fire boss, had pontoons underneath, used to fill up lake water to fight wildfires.

The friends took these pictures of the plane in the lake and the pontoons that broke off from under it — sitting in the water.

Wagner says he was surprised to see the pilot make it out alive, adding, “I thought there wouldn’t be any survivors, you could tell plane underwater, it was in 30 feet of water, I thought it would be a recovery situation.”

Cass County Sheriff Bryan Welk calls the folks who stopped to help good samaritans.

“His plane was sinking right as I got there,” said John Carlson, who helped rescue the pilot. “It was something else.”

Carlson, who lives in the Twin Cities, was up in Cass County taking out the boats from his cabin for the season.

Carlson heard the crash, grabbed his boat keys, and drove out to check it out.

“I saw the plane was not in good shape,“ Carlson said. “I was happy he (pilot) was conscious, and not going down with the plane.”

Carlson helped get the pilot into his boat, as they waited for first responders to arrive, to check him out.

The Sheriff’s Office says so far, the investigation shows the plane was working on a proficiency flight when the crash happened. Authorities add those flights are done routinely to meet minimum flight hours each month.

As of this publishing, crews are still working to retrieve the aircraft and its components.

Multiple agencies are working on the investigation, including the Minnesota DNR, the FAA, and the NTSB.