Moscow ( CNN ) -- A plot to assassinate Russian Prime Minister Vladimir Putin has been foiled , Russia 's state-run Channel One TV reported Monday , less than a week before presidential elections that Putin is expected to win . Citing unnamed sources , the report said a group of plotters was arrested in the Ukrainian city of Odessa in early January and , after weeks of questioning , confessed to planning to kill the Russian leader . The TV report included what it said was a confession by Adam Osmayev , a fixer associated with the two men who were seized in Odessa . `` Our final goal was to come to Moscow and try to organize an attempt on Prime Minister Putin , '' Osmayev said . He said the plan involved using military-grade land mines to blow up vehicles . Channel One showed video of what it said was the raid on Osmayev 's apartment by armed security officers wearing black bulletproof vests and helmets . The video shows Osmayev , with red marks on his back and bloody bruises on his face , kneeling as officers demand his name . Ukraine 's domestic security agency , the SBU , uncovered the plot after an explosion at an apartment building in Odessa killed one of the plotters and injured another , Channel One said . The survivor tipped them off to Osmayev 's involvement , the report said . The plotter who was killed was allegedly willing to be a suicide bomber , and the mission was organized by Chechen militant leader Doku Umarov , Channel One reported . CNN has not independently confirmed the existence of the plot , and a former British ambassador to Moscow expressed doubts about it . `` There was a similar alleged plot against him the election before last , '' Andrew Wood said . `` That 's pretty much ( all ) you need to know . It 's suspiciously convenient . '' Putin has dominated Russian politics for more than a decade , and his opponents accuse him of rigging parliamentary elections late last year . International observers also said that the election was not free and fair , and protests of a size not seen in Russia in two decades followed the vote . Wood said the protests may have encouraged the Kremlin to say there was a plot against Putin 's life to build support for him . `` They 've been taken aback by the degree of opposition , '' said Wood , who is now a Russia expert at Chatham House , a think tank in London . `` Even if he wins this election , which one must assume that he will , it wo n't necessarily mean that he has strong and durable support , '' he said . Wood did not say outright that he did not believe there was really a plot to kill the prime minister . `` It 's conceivable , but it seems improbable . Anything could be true . I ca n't say it 's not true , '' he said . Putin 's spokesman Dmitry Peskov told the Russian news agency Itar-Tass that he confirmed the TV report but would not comment on it . The Russian FSB declined to answer CNN questions about the alleged plot . The announcement comes a week ahead of this Sunday 's presidential election . Putin handed over the presidency to ally Dmitry Medvedev in 2008 , when he was barred from seeking a third consecutive term . After spending four years as prime minister , he announced in December that he would seek the presidency again . Human rights groups say civil liberties and democratic freedoms have suffered during his rule . But opponents took to the streets by the thousands after his United Russia party won a narrow majority in December parliamentary elections , which monitors from the Organization for Security and Cooperation in Europe said were `` slanted in favor of the ruling party . '' The leading opposition candidate in the March 3 vote is Communist Gennady Zyuganov . Russia 's third-richest man , billionaire New Jersey Nets owner Mikhail Prokhorov , and ultranationalist Vladimir Zhirinovsky are also running . Critics of Putin 's showed up in the thousands on Sunday in a show of strength ahead of the election . They attempted to complete a circuit of Moscow 's 15-kilometer ( 9.3-mile ) `` Garden Ring '' road but fell short . The RIA Novosti news agency quoted police as saying 11,000 people turned out Sunday , far below the estimated 34,000 needed to complete the human chain . CNN 's Richard Allen Greene contributed to this report .
A former UK envoy to Moscow says the report is conceivable but improbable . One alleged plotter says the plan was to use military-grade land mines . The plotters were arrested last month in Odessa , Ukraine , Channel One reports . Score: 6