Tsarnaev widow's family home searched by FBI

Katherine Russell, 24, was seen leaving her parents' house in Rhode Island with her lawyers on Monday.

Also, high-profile death penalty lawyer Judy Clarke has joined the defence of Dzhokhar Tsarnaev, Tamerlan Tsarnaev's brother and suspected co-conspirator.

Three people were killed and more than 260 injured in the 15 April blasts.

Ms Clarke is nationally known for her work on high-profile cases.

Most recently she worked on the defence of Jared Loughner, who killed six and severely injured former Representative Gabrielle Giffords, and has also represented "Unabomber" Ted Kaczynski and Atlanta Olympics bomber Eric Rudolph during sentencing, Kazinform cites BBC News.

The younger Tsarnaev has been charged with using a weapon of mass destruction in the dual explosions near the finish line of the Boston Marathon.

Bomb 'evidence'

On Monday, FBI agents at the Russell home retrieved DNA samples, an official told the Reuters news agency.

Investigators are looking for any evidence that would further tie the Tsarnaev brothers to the bombing and spent hours in the family house in North Kingston, Rhode Island.

Ms Russell's lawyer said she was doing everything she could to assist with the investigation. She has lived at her parents' house since Tamerlan Tsarnaev was killed several days after the bombing.

The couple lived with their young daughter in an apartment in Cambridge, Massachusetts. Police say they have found bomb material at the residence.

Ms Russell's lawyers say she did not know much about her husband's activities because she spent most of her time outside the home working as a health aide while he watched their child.

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