Some Kenyan athletes were warned ahead of unannounced doping tests and a banned runner accused athletics officials of demanding money to hide positive tests, German state broadcaster ARD reported on Tuesday.
ARD and Britain's Sunday Times reported recently that the International Association of Athletics Federations (IAAF) had not followed up on hundreds of suspicious doping tests, throwing the sport into turmoil.
ARD has reported on allegations of doping in Kenyan athletics in the past.
In the latest report on Kenyan athletes, Frimin Kiplagat Kipchoge, a former runner who works with athletes, said some testers called up athletes ahead of their visits and were willing to reschedule them if they were not available.
According to doping rules, unannounced tests can take place at any time with the athlete having to register his or her daily whereabouts with a central system so as to be available for drug-testing, both in and out of competition.
Banned athlete Ronald Kipchumba, who tested positive for blood-boosting EPO in 2012, told ARD some athletics officials in the country also were demanding money from them to bury positive tests.
The governing body of athletics has been in crisis since the data from thousands of blood samples was leaked to the two media organizations this month.
Three weeks of further leaks and allegations that the IAAF has been soft on dopers overshadowed the run-up to its biennial showpiece, the world athletics championships, which opened in Beijing last week.
World Anti-Doping Agency (WADA) chief Craig Reedie told ARD Kenyan authorities were aware of what was needed to be done in the fight against doping, when he was asked if WADA would launch a separate investigation into the country's athletes.
WADA has launched two separate investigations into previous ARD allegations of doping.