THE bitter row over doping allegations in athletics has intensified with the two blood experts at the centre of the claims standing by their views despite a fierce attack by Sebastian Coe.

Lord Coe, who is running for the presidency of the IAAF later this month, said there was widespread anger in the sport at claims by German broadcaster ARD and the Sunday Times that athletics had turned a blind eye to hundreds of suspicious blood tests.

The double-Olympic 1500m champion insisted the IAAF had led the way on tackling doping and had accepted the embarrassment of banning some of the top athletes from the sport. A lengthy and detailed response by the IAAF labelled the allegations "sensationalist and confusing''.

The Sunday Times has issued a statement standing by its story and calling the IAAF response "disingenuous". It said it had gained access to a database containing more than 12,000 blood tests from 5000 athletes and that more than 800 athletes – and a third of all medallists in endurance events at recent Olympics and World Championships – had suspicious blood-test results which were not followed up by the IAAF.

The two experts – or "so-called experts" according to Coe – retained by the Sunday Times, Michael Ashenden and Robin Parisotto, said they stood by their beliefs.

In a joint statement they said: "We note the concerns raised by the IAAF with regard to the analyses we undertook of the data. We have rebutted each and every one of their so-called 'serious reservations'.

"We followed the same procedure as IAAF expert panelists when reviewing ABP [athlete biological passport] profiles, classifying results as 'likely doping', when we were able to confidently exclude all other potential causes, or instead 'suspicious', when there was genuine evidence of blood manipulation; however, further investigation, such as target testing, would have been required."

Coe, however, said the IAAF had followed up on the suspicious results which had led to suspensions for a number of leading figures. He also admitted some countries still have a doping problem.

Asked about his statement that the report was a "declaration of war", Coe told BBC Radio Four's Today programme: "I don't think anybody should underestimate the anger that is felt in our sport. We have led the way on this.

"To suggest that in some way we sit on our hands at best, and at worst are complicit in a cover-up, is not borne out by anything we have done in the last 15 years. As a sport we have led the way on out-of-competition testing, on accredited laboratories, we were the first sport to have arbitration panels.

"Yes, we have countries out there that are causing a problem and an inordinate amount of difficulty across our sport but to say we are not investigating or turning a blind eye to this could not be further from the truth."

Asked if that included Russia, which has had a number of high-profile drugs cheats banned, Coe said: "Well that is not the only country which has caused issues in the past. We introduced blood passports in 2009 because we wanted to elevate the science around weeding out the cheats. It is that profile that has chased some of the highest profile athletes out of the sport.

"If [the IAAF experts] deem that profile necessary to take someone out of the sport we will do so. This has not been easy for us this has caused us intense embarrassment but we would rather have short-term embarrassment and protect the clean athletes. That's why our sport is so angry at the moment."

The World Anti-Doping Agency (WADA) insisted the leaked data had not come from its ADAMS system. David Howman, WADA director general, said: "WADA condemns the leak of athlete's confidential information and wants to assure athletes of the world that they can have full confidence in ADAMS in protecting their personal data.

"WADA would also like to reassure clean athletes that atypical blood data, which may appear within this database, is not necessarily indicative of doping. The strength of the ABP is that it measures data over time, aligned with WADA's rules governing the ABP. It would be reckless to draw conclusions on the basis of limited information."