Former Chilean leader Sebastian Pinera, an early front-runner to win back the presidency this year, struck back on Monday at what he called a smear campaign by leftist politicians who have demanded probes into his actions during his first term.
Media reports have linked the center-right billionaire businessman, who is expected to officially announce his presidential bid next month, to two cases of possible improper overlap between his political role and investments.
Pinera has denied any wrongdoing.
Disillusionment with the political and business elite is running high in Chile after a series of scandals in recent years, and any whiff of impropriety could torpedo Pinera's likely leadership bid.
Earlier on Monday, public prosecutors said they may look into a media report that Pinera owned a stake in a mining company in a zone where he had refused permission for a hydroelectric station in 2010, ostensibly for environmental reasons.
They are also looking into allegations that his family invested in a Peruvian fishing company, just before international court hearings over a maritime dispute between Chile and Peru.
A lawmaker in the Communist Party, part of the governing coalition, had asked prosecutors in November to investigate after press reports emerged about the Peru case. The prosecutors said on Monday they had not found evidence to date to proceed with a charge.
At a news conference on Monday, Pinera condemned the accusations and said his actions at no time were illegal or illicit.
"The Communist Party with the complicity of the [governing coalition] is developing a dirty campaign to impede a presidential candidacy," Pinera said. "These false campaigns must end."
Pinera is leading opinion polls ahead of November's vote, and is expected to easily secure the backing of the right-wing coalition.
He faces a stiff challenge from Alejandro Guillier, an independent leftist and senator since 2013, who is surging in the polls as he campaigns on a message of change from politics as usual.
Pinera was president from 2010 to 2014, before being succeeded by his predecessor, center-left Michelle Bachelet.
Consecutive presidential terms are constitutionally barred in Chile.