He said Dzhokhar Tsarnaev was off at college and she saw him "not at all" at the apartment they shared with her mother-in-law.
Katherine Russell Tsarnaev was attending Suffolk University in Boston when friends introduced her to her future husband at a nightclub, DeLuca said. They dated on and off, then married in 2009 or 2010, he said.
She was raised Christian, but at some point after meeting Tamerlan Tsarnaev, she converted to Islam, he said. When asked why she converted, he replied: "She believes in the tenets of Islam and of the Koran. She believes in God."