Leonid Kuchma, who served as president of Ukraine (1994-2005), said he was surprised when he learned from media outlets a criminal case had been brought against him, the Russian news agency RIA Novosti reported.
Kuchma is accused in the killing of journalist Georgy Gongadze whose decapitated body was found in a forest near Kiev in November 2000.
Three former employees of the Interior Ministry were convicted of Gongadze's death in 2008.
Two years later a secret tape surfaced on which Kuchma is heard ordering former Interior Minister Yuri Kravchenko, who died in 2005, to eliminate Gongadze.
"I am morally ready to experience all the torments of hell to prove that I am [not guilty]," Kuchma told journalists after being questioned by prosecutors.
He has been ordered not to leave the country.