(ABC/WSYR-TV) -- Federal authorities Monday searched behind a Cambridge drug store in an area where the brothers’ father used to repair cars, looking for possible explosives or where the bombs were made.
So far, there is no evidence of a continuing threat.
The FBI also wants to question Tamerlan’s wife, who was see over the weekend leaving the family apartment.
A Rhode Island native, 24-year-old Katherine Russell converted to Islam and changed her name from Katherine to Karima.
Because she lived in the same Cambridge apartment where authorities believe the two brothers hatched their plot, she could provide clues about whether others were involved or not.
Her family issued a statement Monday, saying, “We know that we never really knew Tamerlan Tsarneav.”
Local prosecutors said they’re now investigating whether Tamerlan was involved in the brutal murder of three young men, one of whom was his roommate. The three men were found with their throats slashed, covered in marijuana and cash.
Also under investigation, the six month trip Tamerlan took last year to Russia, at a time that rebel groups there carried out a number of violent attacks in the Dageastan region.
Investigators say they want to know whether he met with any of the notoriously fierce extremist leaders there.
Neighbors in Cambridge say Tamerlan was a changed man when he returned to the U.S., swearing off tobacco and alcohol, linking to extremist Jihadist videos and saying, “I don’t have any American friends. I don’t understand them.”
A neighbor said he expressed anger about America and Christianity.
“He said the Bible was a cheap copy of the Koran. He said that most American wars are excused with the bible,” said the neighbor.
The brothers’ mother, Zubeidat Tsarnaev, told ABC News from Russia that Tamerlan was always the leader of her two boys and that after the bombing he called to say, “Everything is okay, thanks to Allah.”