CARACAS, Venezuela (AP):

The leader of a student protest movement that has emerged as a major challenge to Venezuelan President Hugo Chávez has won a US$500,000 prize awarded by a United States-based think tank.

The Cato Institute announced on Thursday that law student Yon Goicoechea was chosen for his leadership as an advocate for freedom and democracy.

The 23-year-old student leader organised protests last year that were widely seen as key to the defeat of sweeping constitutional changes proposed by Chavez in a December referendum.

'Collective prize'

The changes would have let Chavez run for re-election indefinitely and would have granted him broad powers to reshape Venezuela into a socialist state.

"I see it as a collective prize. The prize is being given to me, but it's being given to me as a representative of something much bigger,'' Goicoechea told The Associated Press in an interview ahead of the formal announcement. "I hope that with this we can motivate and strengthen our movement.''