(CNN) When she climbed atop a car this week during a mass sit-in in Sudan, a 22-year-old activist aimed to rouse a crowd already intent on forcing the nation's President to step down, she told CNN.

"I wanted to get (on the car) and speak to the people ... speak against racism and tribalism in all its forms, which affects everyone across all walks of life," Alaa Salah, who is also a journalist, said by phone. "I wanted to speak on behalf of the youth. ... I wanted to come out and say that Sudan is for all."

Just days later, her message has come to symbolize Sudan's protests -- and the prominent role Sudanese women are playing in it -- thanks to a photo of Salah, clad in a white robe and gold moon earrings, that's gone viral. It was snapped as she stood Monday on the vehicle's roof amid hundreds of protesters outside the presidential compound and army headquarters in Khartoum and chanted, as the throng responded, "Revolution!"

"Every time people responded with 'Thawra' ('Revolution'), I would get more excited," Salah said. "We need international support, for people to be aware of what's happening and to understand our demands."

In that moment, Salah was "representing all Sudanese women and girls and she inspired every woman and girl at the sit-in," Lana Haroun, who snapped the image, told CNN. "She was telling the story of Sudanese women. ... She was perfect."

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