On April 15th, 2013, two explosive devices were detonated 12 seconds and 190 meters apart along the marathon route on Boylston Street near the finish line of the 117th Boston Marathon. The bombings killed three civilians and injured hundreds more. At least 14 people required amputations, with some suffering traumatic amputations as a direct result of the explosions.
Three days after the bombings occurred, on Thursday April 18th, at 5:10 PM, the FBI released photographs of two individuals carrying backpacks, walking along the Boston Marathon route, which the agency identified as the only suspects in the bombing investigation. The FBI asked the public for assistance identifying the men.
The suspects would eventually be identified as brothers Tamerlan and Dzhokhar Tsarnaev. The agency contends that it only became aware of Tamerlan Tsarnaev's identity after his death amid the unprecedented manhunt for the bombing suspects. We will examine each suspect's background and aspects of the attack as well as the manhunt in great detail at a further point in the series. For now, we will focus on what was known about the primary suspect, Tamerlan Tsarnaev, prior to the events of April 15th 2013.
Within days of the bombings, the Russian Federal Security Service (FSB) revealed that it had warned the United States about Tamerlan Tsarnaev two years before, in March 2011, when it sent the FBI Legal Attaché in Moscow a letter regarding Tsarnaev.
According to United States Congressional Representative William Keating, the letter sent by the Russian government contained many intimate details regarding Tamerlan Tsarnaev’s background and life in the United States. Among these details were biographic research, marital status, social media analysis, physical addresses, and recorded content of telephone conversations.
The Russian Federal Security Services warned the FBI that it was primarily concerned that Tamerlan Tsarnaev may travel to Russia in order to join the Islamist insurgency in the Caucasus region. The letter sent to the FBI requested that the agency notify the Russian FSB if Tamerlan Tsarnaev is detected leaving the country.
According to the letter sent to the FBI Legal Attaché in Moscow, Tamerlan Tsarnaev “had changed drastically since 2010 as he prepared to leave the United States for travel to the countries region to join unspecified underground groups.”
Writing for the Russian news outlet Novaya Gazzetta, journalist Irina Gordienko stated that Russian officials first became interested in Tamerlan Tsarnaev after discovering evidence of frequent communications between Tsarnaev and William Plotnikov, a known Islamist operating in the North Caucasus region.
William Plotnikov, a former student at Seneca University in Toronto, was reported missing by his parents in Canada in 2010, when Plotnikov traveled to southern Russia in order to join the Caucasus Emirate, an islamist militant group which seeks to establish Islamic rule in the region.
In early 2011, Canadian law enforcement provided the FSB information about William Plotnikov and his activities inside Russian territory. In response, Plotnikov was detained by the Russian security services, and provided them with the names of all his contacts in Canada and the United States who, like him, were English speaking Russian natives who identified with the Caucasus Emirate.Plotnikov provided the names of contacts he had established through an online social network, known as the World Association of Muslim Youth, which contains large amounts of Islamist propaganda associated with Al Qaeda.
Among the names Plotnikov provided to Russian authorities during his interrogation was Tamerlan Tsarnaev.
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How did the FBI handle the warning it received in March 2011? Why wasn't the FBI able to prevent the attack?