Yandarbiev, who briefly served as interim president after the assassination of Chechnya's first separatist leader Dzhokhar Dudaev in 1996, had spent the past several years living in Qatar. Russia had sought his extradition for his alleged masterminding of several attacks in Russia, including the 2002 Dubrovka theater hostage crisis in Moscow.
Three Russian security agents were subsequently arrested in connection with the bombing. One had a diplomatic passport and was released. Debate over the fate of the remaining two, now in Qatari custody, has put a serious strain on Moscow-Doha relations.
Igor Ivanov, who was Russia's acting foreign minister at the time of the arrests, blasted Qatari authorities for holding the two men, who he said were linked to the battle against international terrorists. The Foreign Ministry called the arrests a hostile act and accused Qatar of "connivance" with international terrorists.
Hostilities grew even more heated after Qatari officials accused Russia of detaining two of its nationals while they were transiting through a Moscow airport. The alleged detentions of the two men -- wrestlers who were on their way to Serbia to train for the Summer Olympics -- came the same day it was revealed that Doha had leveled charges against the two Russian agents.
The row prompted the Gulf Cooperation Council (GCC) of Gulf Arab states to express support for Qatar in the row with Russia. GCC foreign ministers pledged solidarity with Qatar in its efforts to further investigate the circumstances of Yandarbiev's killing, and condemned the car blast as "a criminal act with violates religious, moral, and human values."
Last week, the Russian ambassador to Qatar, Viktor Kudryavtsev, complained that a Russian consul had been denied a regular meeting with the detainees on "technical grounds." Russian diplomats are demanding that both men receive medical exams and that a legal team be allowed to visit the detainees. So far, neither of those demands has been met.
The issue is especially sensitive in light of new Qatari antiterrorist legislation adopted just after the Yandarbiev killing. That legislation makes murder and even armed criminal activity punishable by death.
Russia has steadfastly denied any role in Yandarbiev's killing, speculating that the assassination may have been a vendetta from his days in Chechnya or a dispute over corrupt financial ties with the Chechen resistance.
But Yandarbiev's widow, Malika Yandarbieva, says her husband had done nothing while in Qatar to draw the hostilities of fellow Chechens. "He never had any blood-feud enemies. All he was doing was in the open, nothing clandestine or illegal. He was always careful in his statements. And he was against terrorism and violence," she said. "Therefore in his statements he always tried to prevent such things from happening."
RFE/RL correspondent Andrei Babitskii, who has covered extensively Russia's conflict in Chechnya, also dismisses Russia's claims that Yandarbiev's death was somehow tied to the Chechen resistance. He says Yandarbiev was among the small group of influential Chechens who did not use their political power to amass personal wealth:
"Yandarbiev was on the sidelines of political life and tried not to really interfere in the course of events. At the same time, I believe -- I cannot prove it, because I do not have precise information -- but I think he had to have had some connection to the financing of the Chechen resistance, because he remained the most prominent figure of the armed Chechen underground in the Arab world. At the beginning of [Russia's] second war [in Chechnya in 1999], he had been openly collecting resources. And he managed to get quite substantial amounts that he sent to Chechnya," Babitskii said.
Yandarbiev's assassination and the detention of the two Russian security agents has also prompted speculation that Moscow was eager to eliminate a prominent member of the Chechen resistance.
Russia's second war in the breakaway republic has dragged on into its fifth year. Despite a constitutional referendum, presidential elections, and other steps of Kremlin-approved "normalization," the situation in the republic is far from being resolved, and remains a thorn in the side of Russian government.
At Russia's urging, Yandarbiev had recently been put on United Nations and U.S. lists of suspected terrorists. His assassination also coincides with the deaths of two well-known Chechen military commanders, Ruslan Gelaev and Akhmed Basnukaev, both killed earlier this month.
But Edi Isaev, the head of information for the Moscow office of the Kremlin-backed Chechen administration, says he doubts Russian agents were responsible for Yandarbiev's death. Russia, he says, does not fight terrorism with terrorism. "Our country has repeatedly asked the country where he was staying to extradite him because he was wanted here [in Russia]. He was not extradited. That is why we could not take any measures in a foreign state," he said. "Some countries have such practices. But we do not make a practice of tracking down people on most-wanted lists and killing them. It would have been another thing if he had been abducted [to bring him into Russia]. But in this case, it was a terrorist action. I do not want that incident to be attributed to our country."