The 30-count indictment against Dzhokhar Tsarnaev was read by US Attorney Carmen Ortiz:

"The indictment of the grand jury returned today charges the defendant with numerous counts, among them conspiracy to use a weapon of mass destruction resulting in death and using a weapon of mass destruction resulting in death, conspiracy to bomb a place of public use, as well as bombing a place of public use resulting in death. Conspiracy to maliciously destroy property resulting in personal injury and death … "

Ortiz went on to describe how the Tsarnaev brothers, 26-year-old Tamerlan now dead and 19-year-old Dzhokhar planned the carnage.

"On our about March 20, the defendant and his brother traveled to a firing range in Manchester, N.H., where Dzhokhar Tsarnaev rented two 9mm handguns, purchased 200 rounds of ammunition and engaged in target practice," Ortiz said. "On or about April 5, Tamerlan Tsarnaev ordered electronic components on the Internet that could be adapted for use in making IEDs, and had them shipped to the Cambridge residence that he shared with his brother, Dzhokhar. The defendant also downloaded a publication that provided instructions on how to build a bomb."

These devices, said Ortiz, were meant to “shred skin, shatter bone and cause extreme pain and suffering, as well as death.”

"Tamerlan Tsarnaev placed a backpack in front of 671 Boylston St., where Marathon Sports is located, among a dense crowd of marathon spectators," Ortiz continued. "The backpack contained an IED constructed from a pressure cooker, low explosive powder, shrapnel, adhesive, electronic components and other items. At the same time, Dzhokhar Tsarnaev walked to 755 Boylston St., in front of the Forum restaurant, where he also placed a backpack containing a similar kind of IED among another crowd of marathon spectators including dozens of men, women and children."

In addition to federal charges, Dzhokhar Tsaranaev was also indicted by a Middlesex County grand jury on more than a dozen charges, including murder in the shooting death of MIT Police officer Sean Collier. Middlesex County covers Cambridge and Watertown, where the shootout between the Tsarnaevs and police took place on the night of April 18.

The bombs were set off in Suffolk County, but District Attorney Dan Conley says the prosecution of Tsarnaev is best handled on the federal level.

"Given the facts, the circumstances and the many federal statutes available, the most appropriate place to prosecute Dzhokhar Tsarnaev is right here in the federal court," Conley said. "And the United States Attorney and I agree that the most effective avenue for holding this defendant accountable for the lives he took in our city is right here in the federal district court, with a federal prosecution using federal statutes. Tamerlan Tsarnaev's justice will be in the next world, but for his brother, accountability will begin right here in the District of Massachusetts.

The punishment for his alleged crimes could land Tsarnaev in a federal prison for the rest of his life, or he could receive the death penalty.

"That decision is up to the United States attorney general," Ortiz said. "Eric Holder will make that decision."

Ortiz and other law enforcement officials were peppered with questions about the indictments. But I also asked Middlesex District Attorney Marian Ryan if she would comment on the status of her investigation into a 2011 triple murder in Waltham that may be connected to one or more of the Tsarnaevs. She declined.

And then retiring Boston FBI director Richard DesLauriers was asked about the agency’s investigation into the killing, by one of its agents, of a Chechen man, Ibragim Todashev. The shooting occurred in Florida shortly after Todashev alledgely implicated himself and Tamerlan Tsarnaev in the triple murder.

"All I can say about that right now is what we've stated publicly before," DesLauriers said. "There is an FBI shooting review ongoing right now in that matter as there is in any shooting involving an FBI agent. So that is proceeding apace, and the results will be released when that investigation is finished."

The federal arraignment of Dzhokhar Tsarnaev -- who remains in a federal medical facility --  is scheduled for July 10 here at the U.S. Courthouse in South Boston.