The wife of the Orlando nightclub shooter has been arrested by the FBI in connection with the massacre.
Noor Salman was taken into custody Monday morning in the San Francisco Bay area and is facing charges in Florida including obstruction of justice.
A Twitter post from the United States attorney's office in Orlando said Salman will make her initial court appearance on Tuesday morning in Oakland, California.
Noor Salman moved to California after her husband, Omar Mateen, was killed in a shootout with SWAT team members during the June 12 massacre at the Pulse nightclub in Orlando.
FBI agents repeatedly questioned Salman in the aftermath of the shooting about whether she had advance knowledge of her husband's plans.
Salman told The New York Times in an interview published last year that she knew her husband had watched jihadist videos but that she was "unaware of everything" regarding his intent to shoot up the club. She also said he had physically abused her.
"Noor Salman had no foreknowledge nor could she predict what Omar Mateen intended to do that tragic night," her attorney, Linda Moreno, said in a statement.
"Noor has told her story of abuse at his hands. We believe it is misguided and wrong to prosecute her and that it dishonours the memories of the victims to punish an innocent person," Moreno said.
Mateen was the only shooter, and by the time a three-hour standoff with law enforcement had ended, 49 patrons were killed and another 53 people required hospitalisation.
Mateen pledged allegiance to the Islamic State group in a 911 call to emergency officials during the standoff. He also made a series of Facebook posts and searches before and during the attack.
Salman, who grew up northeast of San Francisco, wed Mateen in 2011 after the two met online. They lived in Fort Pierce, Florida, at the time of the shooting. Last month, Salman filed a petition in a California court to change the name of the son she had with Mateen.