BOSTON — Boston Marathon bombing suspect Dzhokhar Tsarnaev downloaded bomb-making instructions from an al-Qaida magazine, gathered online material on Islamic jihad and martyrdom, and later scrawled anti-American messages inside the boat where he lay wounded, a federal indictment charged yesterday.
The 30-count indictment contains the bombing charges, punishable by the death penalty, that were brought against the 19-year-old Tsarnaev in April.
But prosecutors added charges covering the slaying of an MIT police officer and the carjacking of a motorist during the getaway attempt that left Tsarnaev’s older brother, Tamerlan, dead.
“Tamerlan Tsarnaev’s justice will be in the next world, but for his brother, accountability will begin right here in the district of Massachusetts,” Suffolk District Attorney Daniel Conley, whose jurisdiction includes Boston, said at a news conference with federal prosecutors.
Three people were killed and more than 260 wounded by the two pressure-cooker bombs that went off near the finish line of the marathon on April 15.
Dzhokhar Tsarnaev was captured four days later, hiding in a boat parked in a backyard in Watertown.
According to the indictment, he scrawled messages on the inside of the vessel that said, among other things, “The U.S. Government is killing our innocent civilians,” ‘‘I can’t stand to see such evil go unpunished,” and “We Muslims are one body you hurt one you hurt us all.”
The Tsarnaev brothers had roots in the turbulent Russian regions of Dagestan and Chechnya, which have become recruiting grounds for Islamic extremists. They had been living in the U.S. about a decade.
But the indictment made no mention of any larger conspiracy beyond the brothers, and no reference to any direct overseas contacts with extremists. Instead, the indictment suggests the Internet played an important role in the suspects’ radicalization.
Before the attack, Dzhokhar Tsarnaev downloaded onto his computer the summer 2010 issue of Inspire, an online English-language magazine published by al-Qaida, according to the indictment. The issue detailed how to make bombs from pressure cookers, explosive powder extracted from fireworks, and lethal shrapnel.