World athletics president Sebastian Coe said he reacted with "shock, anger and sadness" to this week's allegations of bribery, extortion and doping cover-ups and said the sport faces a "long road to redemption".
Coe, elected as the president of the sport's IAAF governing body in August, has been dealing with the latest crisis to hit athletics after French authorities this week placed his long-serving predecessor Lamine Diack under formal investigation on suspicion of corruption and money laundering.
Senegalese Diack, 82, is alleged to have received more than one million euros ($1.1 million) in bribes in 2011 to cover up positive doping tests of Russian athletes. Diack's family has dismissed what they described as excessive and insignificant accusations.
Briton Coe told BBC Radio Five Live on Sunday: "I was in clear shock and a great deal of anger and a lot of sadness. These are dark days for our sport, but I'm more determined than ever to rebuild the trust in our sport.
"It's not going to be a short journey and the day after I got elected I started a massive review, and understandably in light of the allegations that were made this week that review has been accelerated.
"I'm determined to rebuild and repair the sport with my council colleagues, but this is a long road to redemption."
The IAAF this year vigorously defended itself against allegations of widespread doping in the sport and that it had failed to properly investigate thousands of dubious drugs test results between 2001 and 2012
Coe's comments came as one of the three co-authors of a report by the World Anti-Doping Agency (WADA) into wrongdoing within athletics -- to be published on Monday -- said that the sport is dealing with a "whole different level of corruption" to that which has plagued world soccer's governing body FIFA.
Richard McLaren, a Canadian law professor and sports lawyer who is one of three men investigating allegations of widespread and systematic drug-taking and malpractice in athletics, told the Sunday Times: "Here you potentially have a bunch of old men who put a whole lot of extra money in their pockets -- through extortion and bribes -- but also caused significant changes to actual results and final standings of international athletics competitions.
"This is a whole different scale of corruption than the FIFA scandal."
Soccer's world governing body FIFA has been in turmoil since 14 officials and sports marketing executives, including two FIFA vice-presidents, were indicted by the United States in May.
FIFA President Sepp Blatter and his European counterpart Michel Platini have since been suspended while Swiss authorities investigate the Zurich-based federation's activities. Both have denied wrongdoing.