Tamerlan Tsarnaev, the older brother of Dzhokhar Tsarnaev, both accused of masterminding the tragic Boston Marathon Bombings, has been officially linked to a Waltham triple homicide in 2011 as per the FBI. Tamerlan was killed following a shootout with authorities days after hiding from the marathon aftermath.

According to papers filed by federal prosecutors, Ibragim Todashev told investigators that Tamerlan was a participant in the murders that saw the three victims with their necks slit and their bodies reportedly covered with marijuana. According to the Washintgton Times, “One of the victims was a boxer and friend of Tamerlan Tsarnaev.”

The Boston Herald notes further that prosecutors are trying to block the defense lawyers of Tamerlan’s younger brother, currently facing 30 charges that carry the weight of the death penalty, from obtaining documents related to the Tamerlan’s suspected role in the gruesome slayings, on grounds that it will compromise the current investigation into Dzhokhar’s case.

“Any benefit to Tsarnaev of knowing more about the precise ‘nature and extent’ of his brother’s involvement does not outweigh the potential harm of exposing details of an ongoing investigation into an extremely serious crime, especially at this stage of the proceeding,” wrote prosecutors in the applicable paperwork.

Todashev was shot and killed by FBI in May, after vocalizing Tamerlan’s link to the murders, on grounds that he outright attacked the agents. The allegation towards Tamerlan has only been officially confirmed through the current filings and motions.