NEW : State media : More than 400,000 people attend the Mass . NEW : The Pope is greeted by a crowd of thousands in St. Peter's Square, Vatican City. Silao , Mexico ( CNN ) -- Cheering onlookers wave balloons , flags and banners as the pope arrives . The pope travels to Cuba Monday .
NEW : State media : More than 400,000 people attend the Mass . NEW : The Pope is greeted by a crowd of thousands in St. Peter's Square, Vatican City. Cheering onlookers wave balloons , flags and banners as the pope arrives . The pope travels to Cuba Monday .