A friend who treated the Tsarnaev brothers to dinner hours after they set off bombs at the Boston Marathon pleaded guilty on Tuesday to misleading investigators in the days after the attack by failing to disclose contacts with the pair and deleting his computer files.
Khairullozhon Matanov, 24, of Quincy will be sentenced to 30 months in prison if US District Judge William G. Young accepts the plea agreement signed by Matanov and federal prosecutors.
The judge set a June 18 sentencing date, but said if he rejects the agreement, then Matanov has the option of going to trial and could face as much as 20 years in prison if convicted of all charges.
Matanov, who arrived in the United States from his native Kyrgyzstan in 2010 and worked as a taxi driver, seemed reluctant to plead guilty and told the judge he believed he was innocent, but feared there were "sufficient facts" for a jury to convict him.
Assistant US Attorney Scott Garland said the government has no evidence that Matanov had prior knowledge of the Marathon bombings or participated in them.
However, he said Matanov called his friend, Tamerlan Tsarnaev, 40 minutes after the April 15, 2013, attacks and took him and his brother to dinner that night.
Two days later, Matanov spoke briefly with Tamerlan Tsarnaev twice on the telephone and visited him at his Cambridge apartment.
After the FBI released photographs of the bombing suspects, Matanov recognized the pair, made an unsuccessful attempt to contact Dzhokhar Tsarnaev, and asked a friend to help him delete files from his computer and dispose of a cellphone he had used to contact the brothers, according to prosecutors.
Later, after Tamerlan Tsarnaev was killed during a violent confrontation with police in Watertown and the massive manhunt for his younger brother that followed, Matanov went to Braintree police and revealed his friendship with the brothers and provided their address in Cambridge.
However, prosecutors said Matanov gave misleading information about his recent contacts with the Tsarnaevs, then deleted files on his computer.
Garland said Matanov's actions interfered with the investigation.
Judge Young said it appeared that Matanov may have wasted investigators' time, however "I didn't hear much about throwing the investigators off track."
The judge warned Matanov that even if he was only pleading guilty to avoid a potentially longer sentence, he would be considered guilty of all charges once he changed his plea.
"I am going to believe you are a guilty man to each of these charges," Young said.
"Yes, your honor," Matanov said.
Matanov pleaded guilty to one count of falsifying and covering up a material fact in a federal investigation, and three counts of making a false statement in a federal investigation.
On his way out of the courtroom, Matanov smiled at Virginia Venti of Westwood, whom he befriended while driving a taxi.
Venti said Matanov told her he did not want to spend years in prison, and "he told me if he pleads guilty he would have less time."
Venti said Matanov, who has been jailed since his arrest last May, professed his innocence when she visited him Monday at the Donald W. Wyatt Detention Facility in Central Falls, R.I., but said he felt he had to plead guilty or risk a worse fate if he went to trial.
She said Matanov said he did not know anything about the bombings and misled investigators because he was trying "to distance himself" from the Tsarnaevs.
Shelley Murphy can be reached at Shelley.Murphy@globe.com. Follow her on Twitter @shelleymurph.