The party leader, Afonso Dhlakama, said the attack took place on Friday as his group travelled to Nampula in the northern province of the same name, according to Lusa. Three of his guards were wounded, Dhlakama said.
Lusa did not give more details, and police and Renamo officials could not be reached for comment.
Earlier this month, local media said Dhlakama had escaped without injury after his convoy was attacked by gunmen as he returned from a rally.
Renamo waged a bloody 16-year civil war against the ruling Frelimo party, which ended with a 1992 peace agreement. Tensions have resurfaced in the last few years, including in the run-up to fractious national elections last October, which Renamo lost.