"The First Square Kilometer of Freedom: Change Square, Sana'a, Yemen." Catalina Martin-Chico's exhibition at Visa Pour l'Image recounts the weeks of struggle of "tribal men, students, women, Shia rebels, Southern separatists and social outcasts" against the oppressive government of President Ali Abdullah Saleh.

"I went to Yemen in mid-April," she tells BJP. "At that time, Yemen was still pretty closed to outside journalists. Very few of them had been able to make it in. Myself, I had been waiting for a press visa for six weeks, and I felt that the wait would continue. That's why I decided to go in with a tourist visa."

Martin-Chico had an assignment for Le Monde Magazine. Titled "Yemen: A Farewell To Weapons," the work looked at revolutionary warriors. After filling her images, though, the Cosmos Agency photographer chose to stay for another three weeks, shooting stories fir Elle, Le Monde and "for myself."

Her work is made of several stories or chapters, she tells BJP, because she didn't start paying attention to Yemen these past few months. In fact, she's been working in the country for four years. [See some of her work on catamartinchico.com] "I couldn't imagine not being there to cover the revolution," says Martin-Chico. "Not only from a news point-of-view, but also to tell the stories of these people. I needed to be under the same tents as these warriors, women and tribes; at the hospitals with them after the demonstrations. I needed to be close to them."

Her work has received the International Committee of the Red Cross Visa d'Or Humanitarian Award 2011. "Over and beyond its aesthetic qualities and emotional force, the work of Catalina Martin-Choco depicts, as required by the prize regulations, human suffering and the professionalism and courage of emergency personnel," says Jean-Christophe Rufin, the Committee's chairman.

The injured, brought in by ambulance, car or motorcycle, and the dead are taken to the mosque on Change Square which is now operating as a first aid center. Image © Catalina Martin-Chico / Cosmos / Winner of the 2011 ICRC Visa d’or Humanitarian Award, sponsored by the SANOFI ESPOIR Foundation

Martin-Chico's work was selected by five media organisations - The New York Times, Paris Match, Le Figaro Magazine, Géo, and La Croix - as well as the Snofi Espoir Foundation and the ICRC. She is a member of the Paris-based Cosmos Agency.

"It's a great reward to four years of work and investment," she says. "The prize, of course, will help me to share this work with more people. It will also help me highlight how unknown this country still is."

She wins a €8000 grant, which she says will help her pay her rent and invest in the equipment she needs. "I wouldn't have been able to afford it otherwise. Then, of course, I want to spend more time on some stories and this grant will allow me to do that without having to rely on assignments. That's a real luxury!"

The work is on show until 11 September at Perpignan's photojournalism festival. "I'm very proud to see my work at Visa. I've been coming here every year since 2004. I've always learnt a lot here. I think it really is the perfect place to exchange ideas, to discover new images and new work."

For more information, visit catamartinchico.com.