FAIRBANKS, Alaska — A Douglas C-54 Skymaster airplane carrying two people crashed into the Tanana River near Fairbanks on Tuesday and burst into flames, authorities said. No survivors have been found.

The plane took off in the morning from Fairbanks International Airport. It crashed about 7 miles (11 kilometers) from there and ''slid into a steep hill on the bank of the river where it caught fire,'' according to Alaska State Troopers.

Clint Johnson, chief of the National Transportation Safety Board's Alaska regional office, said it remained unclear what happened in the time between the takeoff and the crash but the tower operator ''saw a large plume of smoke.''

Michaela Matherne was flying from the village of Galena to Fairbanks to catch a flight to New Orleans when her small plane was diverted to verify the coordinates of the crash site.

''When we were in the air there was speculation that it was a cabin that caught fire, maybe a fish camp,'' she told The Associated Press via Facebook Messenger.

''We actually didn't know what we were looking at until after we landed a few minutes later,'' she said. ''We were shocked and saddened to hear that.''

The C-54 is a military version of the Douglas DC-4, which was a World War II-era airplane. The website www.airlines.net said standard passenger seating for a DC-4 was 44 during its heyday, but most have been converted to freighters.

The Federal Aviation Administration described the plane as a Douglas C-54. Troopers identified it as a DC-4.

The NTSB was sending investigators to the site, Johnson said.

Further information such as the flight's purpose and destination was not immediately available.