(CNN) -- A Massachusetts man was arrested Friday on suspicion of obstructing the investigation of the 2013 Boston Marathon bombings, authorities said.
Khairullozhon Matanov, 23, of Quincy is charged with "one count of destroying, altering, and falsifying records, documents, and tangible objects in a federal investigation, specifically information on his computer, and three counts of making materially false, fictitious, and fraudulent statements in a federal terrorism investigation," the U.S. attorney's office for Massachusetts said Friday.
An indictment against Matanov was unsealed Friday.
Authorities say brothers Dzhokhar and Tamerlan Tsarnaev planted bombs at the finish line of the 2013 race. Tamerlan Tsarnaev was killed during a subsequent manhunt that paralyzed Boston. Dzhokhar Tsarnaev has pleaded not guilty to killing four people -- including three killed by the bombings -- and wounding more than 200 others.
Matanov is not charged with participating in the bombings, but with trying to hide his connection to the Tsarnaev brothers.
Outside court Friday, Matanov's lawyer, Ed Haden, said the indictment was based on "unsubstantiated allegations."
"He had no intent to mislead the investigation," Haden said.
According to prosecutors, Matanov knew that investigators would want to talk to him after the bombings, and he allegedly tried to keep the FBI from learning the extent of his friendship and communication with the suspects.
Prosecutors said that Manatov did not know about the bombings beforehand, but about 40 minutes after the blasts, invited and bought dinner for the brothers, according to the indictment.
According to the indictment, once photos of the suspects were released, Matanov viewed them several times on CNN and on the FBI's website before trying to reach Dzhokhar Tsarnaev.
In the hours and days following the bombings, Matanov contacted and attempted to contact the suspects by phone and saw Tamerlan Tsarnaev at least twice, according to the indictment.
Matanov allegedly tried to give away his cell phone to friends and deleted hundreds of videos and documents from his computer and misled police about the extent of to which he knew the brothers.
He also hid that he shared the "philosophical justification for violence" that the Tsarnaev brothers held, the U.S. attorney's office said.
"In addition to deleting information from his computer, Matanov made a number of false statements to federal investigators," the office's statement said.
If convicted, Matanov faces up to 20 years in prison for the destruction of evidence charge, and eight years for each of the false statement counts.
In separate cases, two friends of Dzhokhar Tsarnaev's -- Dias Kadyrbayev and Azamat Tazhayakov -- pleaded not guilty in September to a superseding federal indictment charging them with conspiracy to obstruct justice and obstructing justice with intent to impede authorities.
A third friend, Robel Phillipos, pleaded not guilty to making false statements to FBI agents during the bombings investigation.
Phillipos was free on $100,000 bond and was being monitored electronically; Kadyrbayev and Tazhayakov, Kazakh nationals, were being held without bail.
Authorities accused the trio of helping Tsarnaev after the deadly April 15, 2013, bombing by taking items from his dorm room and keeping them from authorities. Attorneys for the men denied the allegations.
CNN's Frank Bivona contributed to this report.