Prosecutors in Peru are investigating presidential candidate Keiko Fujimori and her American husband for alleged money laundering.

The preliminary probe was opened quietly in March but only became known Friday in a report by Lima-based newspaper El Comercio. It was later confirmed by Peru's chief prosecutor's office.

Specifically, authorities are looking into a series of suspicious financial transactions and campaign contributions worth nearly $1 million.

Fujimori called the accusations baseless and aimed at boosting her opponent, Pedro Pablo Kuczynski, just two weeks before Peruvians go to the polls in what's expected to be a tight contest.

News of the probe comes just two days after a congressman close to Fujimori resigned from his post as secretary general of her Popular Force party over an unrelated money laundering investigation.