Boston police have arrested three 19-year-olds who they believed disposed of materials following the Boston Marathon attacks covering the tracks of the Tsarnaev brothers.

Dias Kadyrbayev and Azamat Tazhayakov, both Kazakh nationals and Robel Phillipos of Cambridge, Massachusetts, were arrested on Wednesday. The Kazakh nationals were already in custody due to immigration issues, having overstayed on their student visas. They had also been questioned in April over their license plate which reads “TERRORISTA#1”.

The Kazakh students are charged with conspiring to obstruct justice by destroying evidence. Phillipos is charged with knowingly and wilfully making false statements to investigators, the Daily Mail reports.

The trio took a backpack of fireworks and a laptop from Dzhokhar Tsarnaev’s dorm room and disposed of it.

However the nature of the charges put against them thus far does not suggest that these young men aided the Tsarnaev brothers in planning the Marathon bombing which killed three people and left 200 injured and maimed.

A source told the Mirror “The FBI suspect the three of them of helping Dzhokhar to evade police following the attacks.

"The offences that they are suspected of imply they were not involved in carrying out the attacks.

“Agents are still looking at who else the two bombers were involved with and have not ruled out they were given help from other people as well.”

The three arrested became involved once the FBI released photographs of Dzhokhar and Tamerlan Tsarnaev. The day these photos were released Kadyrbayev and Tazhayakov removed items from Dzhokhar’s room.

The criminal complaint states that the pair removed the backpack and “agreed to get rid of it after concluding from news reports that Tsarnaev was one of the Boston Marathon bombers.”

They were greeted at the dorm room by his roommate. The three students watched a movie

The students then had a text message conversation with Dzhokhar saying he looked like one of the bomb suspects. He texts back "lol" and "you better not text me back".

According to the court records Kadyrbayev the “decided to remove the backpack from the room in order to help his friend Tsarnaev avoid trouble.”

He took Dzhokhar's laptop to avoid rousing the suspicion of his roommate, who “might think it strange he was just taking the backpack”. The backpack including fireworks, gunpowder and Vaselines were then found at a Dartmouth landfill. It is still unclear what happened to the the laptop.

During multiple interviews, Phillipos lied about various parts of the story, saying his friends never went to Tsarnaev's dorm room and that they didn't remove anything. He then said they went to the dorm but it was locked and they never entered.

Phillipos said he did not realize the gravity of the situation until the three friends arrived at their off campus apartment in New Bedford. He “'started to freak out, because it became clear from a CNN report that we were watching that Jahar was one of the Boston Marathon bombers.”

Dias Kadyrbayev and Azamat Tazhayakov face a maximum sentence of five years in prison and a $250,000 fine, the US Justice Department said.

Robel Phillipos faces up to eight years in prison and a $250,000 fine.

The three men will appear in court on Wednesday afternoon.

Here's ABC news latest reports: