Lord Coe admits these are "dark days" for athletics but has stressed his determination to lead the sport down the "long road to redemption".
It emerged on Friday that the International Association of Athletics Federations (IAAF) ethics commission had brought disciplinary charges against four men, including the son of former president Lamine Diack and the former head of its anti-doping department, amid the corruption crisis engulfing international athletics.
French police had already revealed Diack, who was succeeded as head of the IAAF by Coe at the end of August, was being investigated over an alleged payment of more than one million euros to cover up doping offences by Russian athletes.
Asked on Sunday for his reaction to those developments, Coe told BBC Radio Five Live's Sportsweek programme: "Clear shock, 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 is not going to be a short journey.
"The day after I got elected, I started a massive review. Understandably, in the light of the allegations that have been made, that review has been accelerated and I am determined to rebuild and repair the sport with my colleagues.
"But this is a long road to redemption."News Now - Sport News