BOSTON (CBS/AP) - Three additional suspects were arrested Wednesday in the Boston Marathon bombings investigation.
All three were friends of Dzhokhar Tsarnaev and attended UMass-Dartmouth with him. The charges are related to incidents after the bombings and interfering with investigators.
Azamat Tazhayakov and Dias Kadyrbayev, 19, both of New Bedford, are charged with conspiracy to obstruct justice by conspiring to destroy, conceal and cover up tangible objects, such as a laptop computer and a backpack containing fireworks, belonging to Tsarnaev.
A third suspect, Robel Phillipos, 19 of Cambridge, is charged with willfully making materially false statements to federal law enforcement officials during a terrorism investigation.
Tazhayakov and Kradyrbavev waived request for bail at their arraignment in federal court Wednesday. Both are due back in court May 14.
Phillipos waived his right for a detention hearing and will be back in court on Monday.
"Dias Kadyrbayev absolutely denies the charges," his attorney Robert Stahl said after the arraignment. "As we have said from the very beginning, he assisted the FBI in this investigation. He is just as shocked and horrified by the violence in Boston that took place as the rest of the community is. He did not know that this individual was involved in the bombing."
Related: UMass Suspends Suspect
Stahl says Dias did not immediately recognize Dzhokhar Tsarnaev as the person involved in the bombings.
Azamat Tazhayakov's attorney, Harlan Protass, says his client was shocked to hear that someone he knew was involved in the bombings. "He has cooperated fully with the authorities and looks forward to the truth coming out in this case," Protass said.
After the arrests were announced, Boston Police said there is no threat to the public.
Tazhayakov and Kadyrbayev are originally from Kazakhstan.
They entered the United States on student visas.
The Department of Homeland Security says Tazhayakov entered the United State with an expired student visa on January 20. Tazhayakov failed to alert officials that he was no longer in school, therefore making him ineligible to be in the U.S. on a student visa.
Officials say at the time of re-entry there was no information that suggested he posed a national security or public safety threat.
Kadyrbayev and Tazhayakov face maximum sentences of five years in prison and $250,000 each in fines.
Phillipos faces a maximum sentence of eight years in prison and a $250,000 fine.
According to the complaint unsealed Wednesday afternoon, Tazhayakov and Kadyrbayev admitted to investigators they agreed to get rid of Tsarnaev's backback "after concluding from news reports that Tsarnaev was one of the Boston Marathon bombers."
Read: Complaint 1 (.pdf)
When the FBI released the first photos of the bombing suspects at 5 p.m. on April 18, Kadyrbayev allegedly "texted Tsarnaev and told him that he looked like the suspect on television."
Tsarnaev repsonded with "lol" and other statements Kadyrbayev interpreted as jokes.
Read: Complaint 2 (.pdf)
About an hour later, Tazhayakov, Kadyrbayev, and Phillipos went to Tsarnaev's dorm room. His roommate let them in and told them Tsarnaev had left a couple of hours earlier. They stayed and watched a movie. It was during this time, according to the complaint, they saw a backpack containing fireworks.
"The fireworks had been opened and emptied of powder. Kadyrbayev knew when he saw the empty fireworks that Tsarnaev was involved in the Marathon bombing," the complaint stated.
Kadyrbayev removed the backpack from the room "in order to help his friend Tsarnaev avoid trouble," investigators said. He also took Tsarnaev's laptop and some Vaseline they believed was used to make the bombs.
The three went back to Tazhayakov and Kadyrbayev's apartment, watched more coverage of the manhunt for the suspsects and then decided to throw the laptop and backpack in the trash in a dumpster around 10 p.m., according to the court documents.
They watched a garbage truck empty that dumpster Friday afternoon.
Authorities had recently searched a landfill near UMass-Dartmouth. They revealed in the affidavit that the backpack was found there on Friday, April 26. Inside were firewworks, a jar of Vaseline and a homework sheet from a class attended by Tsarnaev at UMass-Dartmouth.
Earlier Wednesday, lawyers for Tazhayakov and Kadyrbayev said their clients have been extensively interviewed by federal investigators.
The two men appeared via video for a visa violation hearing in immigration court in Boston on Wednesday.
They have been held in a county jail for more than a week on allegations that they violated their student visas while attending UMass-Dartmouth with Dzhokhar Tsarnaev.
The marathon attack was not mentioned in court and their cases were continued.
Their attorneys said afterward that authorities have not indicated their clients had anything to do with the bombings. Federal authorities would not comment.
Attorney Robert Stahl said Tazhayakov and Kadyrbayev were drawn to Tsarnaev because he also spoke Russian.
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