Tens of thousands of Colombians and Venezuelans flocked to a border bridge Sunday for a free concert. It was organized by Grammy-winning rocker Juanes as a way to help heal the worst crisis in Andean relations in decades.

The concert was held atop the Simon Bolivar bridge connecting Cucuta with San Antonio in Venezuela. The show also featured Colombian singer Carlos Vives, Dominican Juan Luis Guerra and Spain's Miguel Bose and Alejandro Sanz. Juanes' idea for the concert arose from a quarrel that erupted March 1. Colombia launched a commando raid against rebel forces camped in neighboring Ecuador.

Venezuela and Ecuador withdrew their ambassadors to Bogota in protest over the border vibration and sent troops to their borders with Colombia.