A woman walking through the streets in a mid-length dress is nothing shocking in most cities in the world.
But a recent photo of exactly that has spread widely - because it was taken in Kabul, Afghanistan.
"I was shocked," says the man who snapped the photo, local journalist Hayat Ensafi. "I knew I had to catch this special moment because I never saw a woman here walking down the streets like this."
Women face severe restrictions on clothing and movement in Afghanistan. After he took the photo, Ensafi tried to talk to the mystery woman.
"But she walked very fast and didn't talk to me at all," he told BBC Trending.
After Hayat posted the photo on Facebook, thousands of people shared and commented on it. Although it's difficult to tell exactly how many people have seen the photo, and what constitutes an online trend in a country with very low internet usage, the BBC's Syed Anwar in Kabul says the woman is a huge topic of conversation.
"We have seen thousands of people talk about it," Anwar says. "Not only on social media but also in the streets people are talking about her, wondering if she is mentally ill or if she is protesting."
Some Facebook commentators read a political motive into her walk.
"It's her body not yours," wrote Siddiq. "Salute her courage. We want to see more women come out like that."
"My body, my right, … no to forced hijab," wrote another Afghan woman.
Others were less supportive.
"We are living in a Muslim country and we can't bear such people like she is," wrote a user named Ahmad.
Conservative women's dress is a relatively recent phenomenon in Afghanistan. During the late 1960s and early 1970s many Afghan women wore a veil but it was not unusual to see short skirts in Kabul.
Women's rights were steadily rolled back under Taliban rule however, and even today full-body coverings such as the burqa are much more common than exposed flesh.
"It's risky for women to walk bare-legged in Kabul," Syed Anwar says. "At the same time, some people have argued that [dressing like this] can pave the way for Taliban propaganda."
Online comments seem to bear this out, with some Facebook users saying the woman's appearance is an example of a decline in morals in the country.
The identity of the woman remains unknown. After the picture was taken, she disappeared, says Hayat Ensafi, the photographer, leaving only the controversy behind.
"The whole city of Kabul is shocked," he says.
Reporting by Anne Herzlieb
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