She is an Avar, from one of the dozens of ethnic groups in Dagestan.

WSJ: Mother of bomb suspects insists sons are innocent

Authorities later identified the Turkish national as Cengiz Yalcin, and the others are Ahmad Avar and Muhammad Adamov.

CNN: Judge in Spain takes statements from terror suspects

Zubeidat Tsarnaeva, the men's mother, is an Avar, the largest of the more than 30 distinct ethnic groups that comprise Dagestan.

WSJ: Boston Suspect Tamerlan Tsarnaev's Dagestan Visit Scrutinized

Two Chechen-Russians -- Eldar Magomedov (also known as Ahmad Avar) and Muhammad Adamov -- whom Spanish security services suspect had been tasked with carrying out an attack, were arrested on a bus travelling towards France.

CNN: Spain 'al Qaeda cell' may have targeted Gibraltar