This post last updated at 3:55 p.m. ET:
A federal grand jury has indicted two men on charges of obstruction of justice related to the Boston Marathon bombing investigation.
The U.S. Attorney's office for Massachusetts made the announcement on Thursday against two students from Kazakhstan, Dias Kadyrbayev and Azamat Tazhayakov, both 19 at the time of the bombing. If convicted, they face up to 20 years in prison.
As we reported early on in the investigation, Kadyrbayev and Tazhayakov, both in the U.S. on student visas, are former classmates of Dzhokhar Tsarnaev's at the University of Massachusetts, Dartmouth. The pair are believed to have thrown out key evidence — a laptop and empty fireworks canisters — that could link Tsarnaev to the bombings.
On April 18, three days after the bombings, Tazhayakov and Kadyrbayev allegedly removed Tsarnaev's backpack and other items from his dorm room "after concluding from news reports that Tsarnaev was one of the Boston Marathon bombers," according to an FBI affidavit.
The indictment, however, says Kadyrbayev received a text from Dzhokhar Tsarnaev suggesting that he go to Tsarnaev's college dormitory room "and take what's there."
It says that authorities later found the items in a New Bedford, Mass., landfill.
Tazhayakov's attorney, Arkady Bukh, said his client has done nothing wrong and that the case against him "sounds like a witch hunt."
In May, we reported that Kadyrbayev's attorney said his client was "shocked and horrified" by the bombing and "absolutely denies the charges" against him.
A third suspect, Robert Philipos, also 19 at the time of the bombings, allegedly lied to federal agents. He is free on $100,000 bail, pending trial.