The incident was one of the deadliest accidents in recent history for Colombia's Air Force, which also injured dozens.
Monday's accident occurred as the Lockheed Martin-built Hercules C-130 was taking off from Puerto Leguizamo on the border with Peru as it transported troops, Defence Minister Pedro Sanchez said on X.
The plane was believed to have suffered an impact near the end of the runway as it was taking off, firefighter Eduardo San Juan Callejas told Caracol, with a wing of the plane later clipping a tree as it was plummeting.
The crash caused the plane to catch fire and detonate some sort of explosive devices on board, he added.
Residents of the remote area were the first to pull out survivors, with videos showing men speeding down a dirt road with wounded soldiers on the back of their motorcycles.
Military vehicles later arrived, though authorities said the crash site was difficult to reach, impeding rescue efforts.
Colombia's Air Force had initially reported a total of 121 people on board, comprised of 110 soldiers and 11 crew members. It was not immediately clear what accounted for the discrepancy with the figures reported by the local authorities.
President Gustavo Petro, in the twilight of his administration, criticised bureaucratic obstacles for delaying his plans to modernise the military.
"I will grant no further delays; it is the lives of our young people that are at stake," he said in a post on X.
"If civilian or military administrative officials are not up to this challenge, they must be removed."
Several candidates in Colombia's upcoming May 31 presidential election offered condolences and called for an investigation.
A spokesperson for Lockheed Martin said the company was committed to helping Colombia as it investigates the incident.
Hercules C-130 planes were first launched in the 1950s and Colombia acquired its first models in the late 1960s. It has more recently modernized some older C-130s with newer models sent from the US under a provision that allows for the transfer of used or surplus military equipment.
The tail number of the plane that crashed matches that of the first of three planes delivered by the US to Colombia in recent years.
At the end of February, another Hercules C-130 belonging to the Bolivian Air Force crashed in the populous city of El Alto, barely missing a residential block. More than 20 people died in that incident.
with DPA
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