Boston Marathon bombing suspect Dzhokhar Tsarnaev told authorities that his sister-in-law, Katherine Russell, played no role in the April 15 blasts, a federal law enforcement official said.

Russell has been under scrutiny since her husband Tamerlan Tsarnaev and his younger brother were accused of planning and carrying out the bombing that killed three people and wounded more than 200.

Authorities are still investigating whether Russell had any involvement. …

She gave up a DNA sample so authorities could compare it to female DNA on a bomb remnant. It was not a match.