Akhmed Bilalov, a former deputy head of Russia’s Olympic Committee, says he has been poisoned with mercury. Bilalov’s claim comes just weeks after he was fired by President Vladimir Putin over huge cost overruns in the construction of a ski jump for the 2014 Winter Olympics in Sochi. The allegations add to the long list of controversies surrounding the upcoming Sochi Olympics.

Americans are struggling to make sense of what occurred in Boston on April 15 and how two young ethnic Chechen immigrants might have become motivated to kill. The result has been an uptick in Islamophobic rhetoric from some corners, but gestures of tolerance from others.

It's been a week since police suspected Boston Marathon bomber Dzhokhar Tsarnaev following a gunbattle that led to the death of his older brother and fellow suspect, Tamerlan. Evidence suggests the ethnic Chechen immigrants may have been independent radicals motivated by resentment of the U.S. wars in Afghanistan and Iraq.

North Caucasus residents appear to have strong misgivings about the alleged involvement of brothers Tamerlan and Dzhokhar Tsarnaev in the Boston Marathon bombings. Despite evidence provided by U.S. investigators, many in the Russian region believe the two were set up by U.S. authorities.

As more details emerge about the backgrounds of the two Boston Marathon bombing suspects, questions are being focused on Tamerlan Tsarnaev and the six months he spent last year in restive southern Russia. Could the experience have solidified his radicalism? RFE/RL correspondent Tom Balmforth is in Makhachkala, the Daghestani capital, and spoke to Tsarnaev’s aunt, Patimat Suleimanova, about her nephew.

Investigators are looking into possible ties between Tamerlan and Dzhokhar Tsarnaev, the Chechen brothers suspected of staging the Boston marathon, and Islamist insurgents in the North Caucasus. The region’s biggest militant group, the Caucasus Emirate has denied involvement. But Ivan Sukhov, a respected North Caucasus expert, says the suspects nonetheless may have been influenced by Islamic rebels.

As media outlets scramble to understand more about the suspected Boston Marathon bombers, Tamerlan and Dzhokhar Tsarnaev, many relatives linked to the family in Makhachkala, Daghestan, are declining to talk to journalists.Nonetheless, the men's father, Anzor Tsarnaev, did speak from an undisclosed location via telephone to RFE/RL’s Tom Balmforth and the Associated Press in Makhachkala on April 21.

Following the death of one of the suspects in the Boston Marathon bombings and the capture of the other, RFE/RL's Kyrgyz Service visited the ethnic Chechen family's former hometown to unravel their peripatetic background.

What do we know about the Tsarnaev brothers -- the ethnic Chechens who are suspected of perpetrating the Boston Marathon bombings on April 15 that killed three people and injured 170 others -- and their ancestral homeland? RFE/RL Central Newsroom Director Jeremy Bransten sat down with Aslan Doukaev, director of RFE/RL’s North Caucasus Service, for some insight.