A mother and her infant son who disappeared in a plane crash in the dense jungle of western Colombia have been found alive and well five days later in what authorities have described as a "miracle".

Nelly Murillo, 18, and her son Yudier Moreno, not yet one year old, were found on Wednesday close to the site where the Cessna 303 crashed on Saturday in thick vegetation near Quibdo in the province of Choco.

"It's a miracle. It is a very wild area and it was a catastrophic accident," Colonel Hector Carrascal, the commander of the Colombian air force in Antioquia, told AFP news agency.

"His mother's spirit must have given him strength to survive."

Murillo and her baby were taken by helicopter to a nearby hospital with minor injuries, said Carrascal, adding that he was stunned they were alive.

"The lady has wounds and minor burns and apparently the child is unharmed," the Colombian air force said in a statement.

The plane's pilot, Captain Carlos Mario Ceballos, died in the crash and rescuers found his body in the aircraft.

They discovered the doors of the plane ajar and suspected that survivors may have clambered out.

A 14-person search-and-rescue team scoured the dense forest before finding the mother and child.

The plane was travelling between Nuqui and Quibdo in western Colombia when it crashed.

Investigators were looking at the cause.

Nelly Murillo, 18, was found in dense forest near Quibdo with her uninjured son five days after the plane crash [EPA]

Source: AFP