ASUNCION, Paraguay — Paraguayan presidential candidate Lino Cesar Oviedo has been killed in a helicopter crash, authorities said Sunday, ending a dramatic political career that included coups and repeated attempts to lead this impoverished country of more than 6 million people.

Oviedo was returning with his bodyguard from a political rally in north Paraguay on Saturday when his pilot ran into bad weather. All three were killed in the crash, said Johnny Villalba, a spokesman for Paraguay’s airport authority.