Azamat Tazhayakov and Dias Kadyrbayev, who are from Kazakhstan, were classmates with Tsarnaev at the University of Massachusetts Dartmouth. They appeared along side him in a recent photograph of a group of young men visiting New York City's Times Square. They were detained April 20 after being questioned in connection with the bombing, which had killed three people and injured more than 260 others a few days earlier.
Tazhayakov and Kadyrbayev have been interviewed at length, twice, by FBI agents and have cooperated fully, said Stahl, a former federal prosecutor. They are not suspects but are being held for violating their student visas by not regularly attending classes, Stahl said. They are being detained at a county jail in Boston.
The Kazakh Foreign Ministry said Monday night that US authorities came across the two while searching for "possible links and contacts" to Tsarnaev, a sophomore at the university.
Also Read
John Hoey, an assistant chancellor at UMass Dartmouth, said Kadyrbayev is no longer enrolled; he was last a student in the fall. Tazhayakov is enrolled.
The pair had lived at an off-campus apartment in New Bedford, about 100 kms south of Boston, and got around in a car registered to Kadyrbayev with a souvenir plate that says "Terrorista (hash)1." The car was pictured on Tsarnaev's Twitter feed in March.
That plate was just a joke gift from some of Kadyrbayev's friends, meant to invoke his penchant for late-night partying rather than his political sentiments, Stahl said.
Stahl said the young Kazakhs didn't see Tsarnaev in the days before or after the April 15 bombing.