A photo of a four-year-old Syrian girl who thought the photographer's camera was a gun is breaking hearts across the Internet.

The child, who has her arms raised in surrender, was snapped by Turkish photographer Osman Sagirli at the Atmen refugee camp on Syria's border with Turkey last December and went viral this week after being shared on social media.

The child has been identified as Adi Hudea, whose father died in the 2012 Hama massacre and who has been living with her traumatised mother and three siblings 150km away from her hometown at Camp Atmen ever since.

The image was tweeted by Nadia Abu Shaban, a photojournalist based in Gaza and received a rapid emotional response.

"Unbelievably sad", and "humanity failed", the comments read.

"I'm actually weeping seeing this. We've made this planet a horrible place, haven't we?", said one commenter, as another said: "We are failing the younger generations and those still to come. SHAME ON US."

The image has been shared more than 16,000 times.

Accusations that the photo was fake, or staged, soon followed, according to BBC Trending, which spoke to the photographer, now working in Tanzania.

"I was using a telephoto lens, and she thought it was a weapon," Sagirli told the BBC.

"İ realised she was terrified after I took it, and looked at the picture, because she bit her lips and raised her hands. Normally kids run away, hide their faces or smile when they see a camera."

He says he finds pictures of children in the camps particularly revealing.

"You know there are displaced people in the camps. It makes more sense to see what they have suffered not through adults, but through children. It is the children who reflect the feelings with their innocence."

The image was first published in the Turkiye newspaper in January, where Sagirli has worked for 25 years, covering war and natural disasters outside the country. It was widely shared by Turkish speaking social media users at the time, said the BBC.