Late Boston bomber suspect Tamerlan Tsarnaev would often call his wife names, and act on his erratic and violent behavior, her friends told National Public Radio's Laura Sullivan.

Three women who were close friends and roommates of Katherine Russell, and also knew Tsarnaev for several years while they were in college, spoke to the reporter about the 26-year-old suspected bomber.

They said Tsarnaev was "very controlling and very manipulative" of Russell, and said he was "combative and angry," according to the Sullivan. Tsarnaev would often call Russell names such as "slut" and "prostitute." The three women also recalled fights Tsarnaev and Russell would get into where he would sometimes throw furniture or other objects.

The friends said ometime around 2008 Tsarnaev became very religious and stopped going out with them to party, and he also gave up drinking and smoking. At that point they said he "demanded" that Russell convert to Islam, and she complied.

Before 2008 Tsarnaev did not seem to have a particular political standpoint, but starting in 2008 and 2009, they said he had "an extremist point of view," in Sullivan's words. Tsarnaev started talking about being angry with the government and he felt like Islam was under attack.

The last comment echoes what his brother admitted to authorities on Monday. Dzhkohar Tsarnaev, 19, told officials that Tamerlan orchestrated the Boston Marathon bombings and wanted to defend Islam from attack.

Russell has a 3-year-old daughter from Tamerlan named Zahara. Her friends said Russell got pregnant in her senior year of college and dropped out, never earning her degree. Records show she attended Boston's Suffolk University from 2007 to 2010, but she did not graduate.

Russell distanced herself from her friends and also cut off contact with her family members.

Tamerlan was arrested on charges of assault and battery in 2009, but that was with his ex-girlfriend Nadine Ascencao. The charges were dismissed before trial.

Tags: katherine russell tamerlan tsarnaev