Thousands of Colombians march through the streets of the capital, Bogota, to mark International Workers' Day. "There is too much turnover of workers without job stability, salaries that do not compensate. Many young people are migrating," says Percy Oyola, President of the General Confederation of Labor. IMAGES AND SOUNDBITES TO COMPLETE VIDI34QL2N2_EN, VIDI34QK4BF_EN, VIDI34QJ7V2_EN