Ecuador presidential candidate Fernando Villavicencio, a vocal critic of corruption and organized crime, was killed at a campaign event on Wednesday, authorities said, amid an upsurge in violence in the Andean nation blamed on drug traffickers.

QUITO, Aug 9 (Reuters) - Ecuador presidential candidate Fernando Villavicencio, a vocal critic of corruption and organized crime, was killed on Wednesday evening during a campaign event in the north of the capital Quito, authorities said.