Three friends of Boston Marathon bombing suspect Dzhokhar Tsarnaev were arrested Wednesday for allegedly removing a backpack and a laptop from Tsarnaev’s dorm room after the attacks.

According to a criminal complaint released by the FBI, Azamat Tazhayakov and Dias Kadyrbayev, both 19, are charged with conspiring to obstruct justice. Robel Phillipos, 19, is charged with making false statements to federal investigators.

The accused, who began attending the University of Massachusetts at Dartmouth with Tsarnaev in 2011, appeared in federal court Wednesday afternoon.

This FBI photo of fireworks was included in an affidavit in the investigation into the Boston Marathon bombing. The FBI says the fireworks were found in a backpack that belonged to suspect Dzhokhar Tsarnaev.

According to the affidavit, “all three have admitted that on the evening of April 18, 2013, they removed Tsarnaev’s backpack from Tsarnaev’s dormitory room.”

Tazhayakov and Kadyrbayev then agreed to get rid of the backpack after concluding from news reports that Tsarnaev was one of the bombing suspects, the affidavit alleges.

The backpack contained fireworks that had been emptied of powder, according to the affidavit.  Kadyrbayev also took Tsarnaev’s laptop.

Both the backpack and the laptop were placed in a garbage bag and thrown into a dumpster.

Tazhayakov and Kadyrbayev, who came to the U.S. from Kazakhstan, have been held in jail for more than a week on allegations that they violated their student visas.

Tazhayakov left the U.S. in December and was allowed back into the country Jan. 20, even though he no longer had a valid student visa, a federal law enforcement official told The Associated Press.

Phillipos, a U.S. citizen, is accused of lying to federal agents about his April 18 visit to Tsarnaev’s dorm room with Tazhayakov and Kadyrbayev. 

The University of Massachusetts at Dartmouth said Wednesday it has suspended Tazhayakov, "pending the outcome of the case." The school said Kadyrbayez and Phillipos aren't enrolled.

None of the men arrested is accused of any direct involvement in the bombings. However, a footnote in the FBI affidavit states that Tsarnaev told Tazhayakov and Kadyrbayev that he knew how to make a bomb.

Kadyrbayev’s lawyer, Robert Stahl, told reporters outside court that his client was trying to co-operate with investigators and will dispute the charges against him.

Tazhayakov’s lawyer, Harlan Protass, also said his client was co-operating with the investigation.

After the arrests, Boston police issued a statement Wednesday morning emphasizing that there is “no threat to public safety.”

The twin blasts at the Boston Marathon occurred near the finish line of the famed race, killing three people and injuring more than 260 others.

Dzhokhar Tsarnaev is currently being held at a federal medical detention centre outside of Boston. Tsarnaev, a 19-year-old student, is charged with using a weapon of mass destruction to kill, a crime that carries a potential death sentence.

Tsarnaev and his brother, 26-year-old Tamerlan Tsarnaev, were named as suspects by the FBI three days after the bombings.

Days later, authorities say surveillance tape recorded the suspects robbing a convenience store near the Massachusetts Institute of Technology campus, where a university police officer was shot to death while responding to the robbery. That led to a massive manhunt, where Tamerlan Tsarnaev died during a gunfight with authorities and Dzhokhar Tsarnaev was captured alive, but badly injured.

U.S. President Barack Obama said during a news conference on Tuesday that his staff is reviewing intelligence gathered before the deadly bombings took place to determine whether more could be done to prevent future terror attacks.

"We want to go back and we want to review every step that was taken," Obama said. "We want to leave no stone unturned. We want to see, is there in fact additional protocols and procedures that could be put in place that would further improve and enhance our ability to detect a potential attack."