Peru’s presidential election result will not be finalized until mid-May as electoral authorities review more than 15,000 challenged ballots.

With 93% of votes counted, Keiko Fujimori leads the race with about 17%, but the contest for second place remains close between Roberto Sanchez and Rafael López Aliaga.

The top two candidates will advance to a runoff under Peru’s electoral system.

Some candidates have raised concerns about the process, including allegations of fraud and calls for investigation, though no evidence has been presented, Al-Jazeera has reported.

Despite delays and disputes, international observers have said the election generally met democratic standards.