A close friend of suspected Boston Marathon bomber Dzhokar Tsarnaev pleaded guilty last week to impeding the bombing investigation. At a court hearing Thursday, Dias Kadyrbayev admitted to destroying evidence that could be used to implicate Tsarnaev.

Kadyrbayev was indicted along with Azamat Tazhayakov for obstructing the investigation into last year's deadly Marathon bombings that killed three people and injured approximately 260 others. Kadyrbayev and Tazhayakov, both nationals of Kazakhstan, attended the University of Massachusetts Dartmouth (UMass) and were in the United States on student visas.

Soon after the FBI released photographs of the suspected bombers, Kadyrbayev admitted to exchanging text messages with Tsarnaev. In the messages, Tsarnaev said to Kadyrbayev, "I saw the news…" and "If yu [you] want yu [you] can go to my room and take what's there J but ight [night] bro Salam aleikum."

Kadyrbayev then went with co-conspirator Tazhayakov and a third man to Tsarnaev's UMass dorm room. Kadyrbayev found a backpack containing fireworks and a jar of Vaseline. "The fireworks appeared to have been opened, manipulated and some explosive powder appeared to have been removed," Kadyrbayev's plea agreement said. In addition to the backpack, Kadyrbayev also found Tsarnaev's laptop. He and Tazhayakov agreed to take the backpack and the laptop from the dorm room.

Following television news reports on the bombings and the manhunt for the alleged bombers, Kadyrbayev and Tazhayakov agreed to get rid of the backpack and fireworks. They "placed the backpack and its contents, including the fireworks, into a large trash bag and threw the entire bag into the garbage dumpster." But they kept the laptop and hid it in their apartment. A sanitation truck removed the garbage dumpster from their Carriage Drive apartment complex moved its contents to a landfill in New Bedford, Mass. Tsarnaev's backpack, containing fireworks, a jar of Vaseline, and a thumb drive were later discovered by investigators at the landfill.

Under terms of the plea agreement, prosecutors will recommend a sentence of seven years in prison for Kadyrbayev, who has agreed to be deported from the United States after his release. The sentencing date has been set for Nov. 18.