This is a representational image. Gulftoday

The father of two of the four Indigenous children who survived for 40 days in the Amazon has been charged with sexually abusing his stepdaughter, Colombian prosecutors announced.

The siblings were the only survivors after their plane crashed in the jungle in May, killing all three adults onboard, including their mother.

During judicial proceedings on Saturday, the Colombian Prosecutor's Office accused Manuel Ranoque of "abusing his stepdaughter" Lesly since she was 10 years old.

Lesly, now 13, was credited with keeping her siblings alive during their five-week ordeal using her deep knowledge of the jungle and its many dangers -- including snakes, predatory animals and armed criminal groups.

The children, members of the Huitoto Indigenous group, managed to subsist on a package of cassava flour they found on the plane and wild fruits.

Ranoque, who was arrested Friday and denies the charges, is to remain in custody, prosecutors said.

He participated in the massive search operation to track down Lesly, nine-year-old Soleiny, five-year-old Tien Noriel, and Cristin, who is one.

After the children were miraculously discovered about five kilometers (three miles) from the crash site, a custody battle ensued between their maternal grandparents and Ranoque, who is the biological father of the two younger siblings.

The children spent a month recovering in hospital and were then placed in the custody of the Colombian Family Welfare Institute, which detected the possible sexual abuse and informed prosecutors.

William Castro, the governor of the Indigenous village where the family lived, told a local television station at the end of June that "there were indications" that Ranoque had abused Lesly.