Spanish photographer Samuel Aranda has won the World Press Photo 2011 first prize.
His image is of a Yemeni woman cradling an injured relative amid clashes between anti-government demonstrators in Sanaa.
Aranda, who works for photo agency Corbis, captured the snap in October last year while on an assignment for the New York Times.
Chairman Aidan Sullivan said: "The winning photo shows a poignant, compassionate moment, the human consequence of an enormous event, an event that is still going on.
"We might never know who this woman is, cradling an injured relative, but together they became a living image of the courage of ordinary people that helped create an important chapter in the history of the Middle East."
"It stands for Yemen, Egypt, Tunisia, Libya, Syria, for all that happened in the Arab Spring," said juror Koyo Kouoh. "But it shows a private, intimate side of what went on, and it shows the role that women played, not only as caregivers, but as active people in the movement."
The contest has been held for 55 years and according to the official website, it encourages "The highest standards in photojournalism.
"The contest creates a bridge linking the professionals with the general public. As the announcement of the winners makes headlines around the world, so the inspirational role of photojournalism is highlighted to an audience of hundreds of millions."
For a comprehensive list of winners click here.