More than a half-century later, a new documentary is calling into question who took it — and the retired Associated Press photographer long credited for the photo insists it was his, while his longtime employer says it has no evidence of anyone else being behind the camera.

The world-famous AP photo of Kim Phuc — “The Terror of War,” known popularly as “Napalm Girl” — was taken on June 8, 1972, and credited to Nick Ut, a young Vietnamese AP staffer working in the Saigon bureau. The image is among the most recognized and celebrated works of photojournalism of the 20th Century.