Plenty of new information emerged this week about the investigation into the Boston Marathon bombings, including details of a different plot and the arrests of three more suspects. While many questions remain, here's what we learned from official statements or conversations between law enforcement authorities and CNN reporters this past week:
The Boston Marathon was not the original target, one of the brothers suspected in the bombings told investigators. Dzhokhar Tsarnaev and his brother, Tamerlan, initially considered a suicide attack on Boston's massive Independence Day celebration, which draws about 500,000 people.
The brothers chose the Boston Marathon only a day or two before the event once their bombs were ready sooner than expected, a U.S. law enforcement official regularly briefed on the investigation said.
It was also revealed this week that the bombs were built in the apartment where Tamerlan Tsarnaev lived with his wife and child, Dzhokhar Tsarnaev told investigators, according to that law enforcement official.
Three of Dzhokhar Tsarnaev's friends on Wednesday were charged in connection with the bombing: two for allegedly conspiring to discard potentially incriminating items from Tsarnaev's dorm room, and a third for making false statements to investigators.
Dias Kadyrbayev saw the pictures of the suspects released by the FBI and texted Dzhokhar Tsarnaev to tell him "he looked like the suspect on television," according to an affidavit filed in the case. Tsarnaev texted back "lol" and added, "come to my room and take whatever you want."
Kadyrbayev and Azamat Tazhayakov and Robel Phillipos went to his room and removed items, the document states.
A lawyer for Kadyrbayev told CNN that his client turned over a laptop belonging to Dzhokhar to police.
All began attending the University of Massachusetts Dartmouth in 2011, along with Tsarnaev.
The surviving suspect in the bombing is now at a prison hospital, where he is able to speak and interact with the staff, a prison spokesman revealed this week.
His condition has improved, compared to when he arrived at a Boston hospital after a standoff with police.
A source told CNN this week that Dzhokhar Tsarnaev was semi-conscious, wrapped in field gauze and "covered in blood" when he arrived at Beth Israel Hospital.
Tsarnaev appeared to have lost a great deal of blood and was making no sound until he reached the Red Zone Trauma Area, where he began to moan in considerable pain, said the source, a senior employee at the hospital. He didn't seem to utter any words, the source said.
Tsarnaev's defense team now includes Judy Clarke, one of the nation's foremost experts on keeping clients off death row.
Tamerlan Tsarnaev's body laid unclaimed until Thursday, when an extended family member arranged for a funeral home to pick up the body, the Massachusetts office of the chief medical examiner said.
Tsarnaev's cause of death will not be released until the death certificate is filed with the Boston city clerk.