The investigation into the April 15 bombings at the Boston Marathon is widening, with authorities looking at about a dozen people to see if they might have helped the two main suspects either before or after the attack, law enforcement officials familiar with the probe tell NPR's Dina Temple-Raston.
At the same time, officials tell Dina, they do not think Mikhail Allakhverdov -- the man known as Misha -- played any part in the attacks. As we reported Monday, while some relatives of the Boston Marathon bombing suspects have alleged that Allakhverdov turned suspect Tamerlan Tsarnaev toward radical Islam, Allakhverdov told a writer for The New York Review of Books that he did no such thing, had not had contact with Tsarnaev in the past three years and would have tried to stop the bombings if he had known about them.
According to Dina, law enforcement officials say investigators have also spoken with Allakhverdov -- an Armenian convert to Islam who is now living in Rhode Island. Officials say he has been helpful in the investigation, volunteering to turn over his computer and providing more information about Tsarnaev. Allakhverdov is no longer a "person of interest," officials say.
Tamerlan Tsarnaev, 26, and his 19-year-old brother Dzhokhar are suspected of having placed two bombs near the finish line of the marathon. The subsequent explosions killed three people and wounded more than 250. On April 18, authorities say, the brothers shot and killed a MIT campus police officer. Tamerlan Tsarnaev died early on April 19 from injuries he received during a gun battle with police in the Boston suburb of Watertown, Mass. Dzhokhar Tsarnaev was captured in Watertown after an all-day manhunt that shut down much of the Boston metropolitan area. He has been charged with using a weapon of mass destruction and is being held at a federal prison medical facility near Boston.
Officials tell Dina that among those being investigated are two students from Kazakhstan who were friends of the Tsarnaev brothers. The two students were arrested in New Bedford, Mass., shortly after the bombings and are being held on immigration charges.
Another thread in the investigation, as we said Monday, involves Tamerlan Tsarnaev's wife:
"The Wall Street Journal is reporting that investigators found female DNA on at least one of the bombs used in Boston. It's unclear whom the DNA belongs to or whether that person helped carry out the attacks. The newspaper also reported that the FBI collected a DNA sample from Katherine Russell, the widow of Tamerlan Tsarnaev, the older brother who died in a shootout with police. She is said to be cooperating with investigators."
Some related headlines:
-- "Nation's Top Spy Orders Broad Review Into U.S. Government Handling Of Intelligence Information Before Boston Marathon Bombings." (The Boston Globe)
-- "Tsarnaev Family Received $100,000 In Benefits." (The Boston Herald)
-- "Marathon Bombing Investigation Turns Again To Rhode Island." (The Providence Journal)
-- Noted Death Penalty Lawyer, Who Represented Unabomber And Others, Joins Tsarnaev's Defense Team. (Bloomberg News)