An exiled Iranian dissident on Saturday said Iran's newly elected president — already accused of taking American diplomats hostage 36 years ago — played a key role in the 1989 execution-style slayings of a Kurdish opposition leader and two associates in Vienna.

However, a top adviser to outgoing reformist President Mohammad Khatami (search), denied that President-elect Mohmoud Ahmadinejad (search) was involved in the Vienna killings. He also said the new president was not involved in the hostage-taking.

"I'm opposed to Ahmadinejad's policies and thinking, but he was not involved in the hostage drama nor in the assassination of an Iranian opposition Kurdish leader in Vienna," said Saeed Hajjarian (search), the Khatami adviser, who was reached Saturday in Tehran.

Austria's daily Der Standard, meanwhile, quoted a prominent Austrian politician as saying authorities have "very convincing" evidence linking Ahmadinejad to the attacks in Vienna in which the Kurds were killed.

The reports follow recent accusations from some of the 52 Americans who were held hostage for 444 days in Iran beginning in 1979 that the hard-line Ahmadinejad was among the hostage-takers.

Neither Ahmadinejad nor his aides could be reached Saturday for comment on the claims surrounding the Vienna killings, but the president-elect on Friday denied a role in the hostage-taking.

"It is not true," Ahmadinejad said. "It is only rumors."

Alireza Jafarzadeh, who runs Strategic Policy Consulting, a Washington-based think tank focusing on Iran and Iraq, said Ahmadinejad was a Revolutionary Guard commander who supplied the weapons used to gun down Iranian Kurdish politician Abdul-Rahman Ghassemlou and two colleagues on July 13, 1989 in Vienna.

Jafarzadeh is a former U.S. representative for the National Council of Resistance of Iran. The council is the political arm of the Mujahedeen Khalq, a group that Washington and the European Union list as a terrorist organization.

Ghassemlou, the principle target, was secretary-general of the Democratic Party of Iranian Kurdistan. His delegation had been in Vienna for secret talks with envoys from the Tehran regime.

Jafarzadeh said his assessment was based on Iranian government sources "who have provided accurate information in the past."

Jafarzadeh said Ahmadinejad helped organize the Vienna attack while serving in the Revolutionary Guard's Ramazan garrison near the western Iranian city of Kermanshah.

"While he was there, he became involved in terrorist operations abroad and he led many, many operations," Jafarzadeh said.

In 2002, Jafarzadeh disclosed information about two hidden nuclear sites in Iran that helped uncover nearly two decades of covert atomic activity and prompting fears Tehran is trying to build a nuclear bomb.

Der Standard reported Saturday that Peter Pilz, a top official with Austria's Green Party, accused the Ahmadinejad of traveling to Vienna a few days before the slayings to deliver the weapons to the Iranian commandos who carried out the killings. He said he wants a warrant issued for Ahmadinejad's arrest

Pilz could not be reached for comment Saturday, and calls to Austria's Interior Ministry and the nation's federal counterterrorism agency went unanswered.

Pilz said an unidentified Iranian journalist living in France was contacted in 2001 by one of the alleged gunmen, described as a former revolutionary guard who has since died. The gunman's account — which Pilz said strongly implicated Ahmadinejad — was turned over to Austria's federal Office for Counterterrorism and Constitutional Protection.