Dzhokhar Tsarnaev

Dzhokhar Tsarnaev, the Boston Marathon bombing suspect who was arrested days after the attack last month, scrawled a note on one wall of the boat where he was hiding before being taken into custody, CBS News reports.

Dzhokhar Tsarnaev claims brother masterminded Boston Marathon bombings

In the message, Tsarnaev takes responsibility for the attacks and says they were motivated by U.S. military action in places like Iraq and Afghanistan, according to CBS. "When you attack one Muslim, you attack all Muslims," he reportedly wrote, referring to the victims of the Marathon bombings as "collateral damage." Three people were killed and more than 250 injured in the attacks.

Authorities are speculating that the message was a suicide note as well as a confession, according to CBS. In it, Tsarnaev references his older brother Tamerlan, who was killed in a shootout with police the day before Dzhokhar was arrested. Dzhokhar refers to his brother as "a martyr in paradise" and writes that he will soon be joining him, CBS reports.

Dzhokhar Tsarnaev formally charged in Boston Marathon bombings

Watch the CBS report below: 

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