A Palestinian reveller takes part in a colours festival organized by Palestinian activists in the West Bank city of Ramallah August 20, 2015. The festival is inspired by the Hindu spring festival of Holi. (Photo by Mohamad Torokman/Reuters)

Palestinian revellers take part in a colours festival organized by Palestinian activists, in the West Bank city of Ramallah August 20, 2015. (Photo by Mohamad Torokman/Reuters)

Palestinian revellers take part in a colours festival organized by Palestinian activists in the West Bank city of Ramallah August 20, 2015. (Photo by Mohamad Torokman/Reuters)

A Palestinian reveller takes part in a colours festival organized by Palestinian activists in the West Bank city of Ramallah August 20, 2015. (Photo by Mohamad Torokman/Reuters)

A Palestinian reveller smokes a cigarette as he takes part in a colours festival organized by Palestinian activists in the West Bank city of Ramallah August 20, 2015. (Photo by Mohamad Torokman/Reuters)

A Palestinian reveller takes part in a colours festival organized by Palestinian activists in the West Bank city of Ramallah August 20, 2015. (Photo by Mohamad Torokman/Reuters)

Palestinian revellers take part in a colours festival organized by Palestinian activists in the West Bank city of Ramallah August 20, 2015. (Photo by Mohamad Torokman/Reuters)

Palestinian revellers hold bags of coloured powder during a colours festival organized by Palestinian activists in the West Bank city of Ramallah August 20, 2015. (Photo by Mohamad Torokman/Reuters)