Opponents say Toledo's whirlwind trips ahead of Sunday's elections are a throwback to former President Alberto Fujimori, who was accused of influencing voters with new highways and school inaugurations during election campaigns.

Election laws were revamped in an attempt to prevent future campaign abuse after Fujimori's decade-long regime collapsed when he fled to Japan amid a corruption scandal in 2000.

Toledo, who rose to prominence as an opponent to the authoritarian Fujimori, denied any impropriety.

"I will continue doing my work and not allow candidates to participate with me," he said.

Observers from the Organization of American States in Lima to watch Sunday's elections described the reprimand as a "healthy dynamic."

"This indicates that elections officials act," OAS delegation leader Diego Paz said on Wednesday.

in its declaration, the National Board of Elections ordered its officials in Andahuaylas, Piura, Cajamarca and Ayacucho — regions recently visited by Toledo — to file complaints made there with the Attorney General's office.