By Madison Park

CNN

(CNN) -- For months, questions have surrounded Noor Salman, the widow of Pulse nightclub shooter Omar Mateen.

What did Salman know of her husband's plans? Could she have said something or tipped off authorities to prevent the deadliest mass shooting in US history? Or is she a victim of Mateen's abuse, as her attorney maintains?

Different portrayals of Salman have emerged since her husband killed 49 people and injured more than 50 others at Pulse, a gay nightclub, in June.

Salman was arrested Monday in California on federal charges that include obstruction of justice and aiding and abetting her husband's material support to ISIS. Authorities believe Salman acted of her own free will and knowingly took steps to obstruct the investigation, according to a law enforcement official.

"I knew within days that she had some part and aided Omar Mateen in this horrific tragedy and that some day, when the investigation was complete, she would be put behind bars and ultimately answer for this horrific tragedy," Orlando police Chief John Mina said.

Salman's attorney, Linda Moreno of Tampa, Florida, denies that her client knew anything about what her husband planned to do. Moreno described a wife who had endured her husband's abuse.

Noor Salman's marriage

• Salman was Mateen's second wife.

• She grew up in Rodeo, California, a suburb of San Francisco, after her parents had immigrated from the West Bank in 1985, according to The New York Times.

• She was one of four daughters of a small businessman. She earned an associate degree in medical administration at a local college, the newspaper reported.

• Salman told the Times she met Mateen on a dating site called Arab Lounge in 2011. They married that year.

• Salman and Mateen settled in Fort Pierce, Florida, about a two-hour drive from the Orlando nightclub. They have a son, who was 3 at the time of the massacre.

• Salman was abused by Mateen, her attorney said in a statement issued after her arrest. "Noor has told her story of abuse at his hands. We believe it is misguided and wrong to prosecute her and that it dishonors the memories of the victims to punish an innocent person."

• Mateen's ex-wife, Sitora Yusufiy, described a brief but violent relationship to a mentally ill man whom she was only able to escape from through her family's help. She said he was physically abusive and a steroid abuser.

Conflicting accounts

Early in the investigation of the massacre, FBI investigators did not consider Salman as a co-conspirator but suspected she may have known of his intentions, a law enforcement official told CNN.

Salman gave conflicting accounts about what she knew of Mateen's intentions in the hours before the attack, authorities said. She told the FBI her husband said he wanted to carry out a jihadist attack. But she denied knowledge of his plans, a law enforcement official told CNN last year.

She initially denied that when Mateen left the house on the night of the attack she had any idea he was going to do something violent.

But in subsequent statements, Salman conceded she had a suspicion he might be planning an attack, the officials said. According to one official, she knew "for a while" Mateen had thoughts of wanting to do something violent. He had been talking about it for months, if not years.

Actions before the attack

Months before the attack, Mateen added Salman's name to his life insurance policy and made sure she had access to his bank accounts, two law enforcement officials said. He also bought her an expensive piece of jewelry, the sources said.

She told investigators that in the weeks leading up to the attack, Mateen spent thousands of dollars, buying among other things the guns used in the massacre.

Law enforcement officials said Salman accompanied Mateen on trips to scout potential targets, though it is unclear how much she knew about his intentions. She was with him when he visited Pulse and Disney Springs, an entertainment and shopping complex, earlier in 2016.

"Noor Salman had no foreknowledge nor could she predict what Omar Mateen intended to do that tragic night," said Moreno, her attorney, in a statement after Salman's arrest.

Two hours after the attack started at Pulse, Mateen texted his wife at 4 a.m. and asked her whether she had heard any news about the shooting.

At one point, Salman told Mateen that she loved him. She tried calling her husband several times during the standoff, a law enforcement official said.

Mateen didn't answer.

CNN's Dan Simon, Holly Yan, Pamela Brown and Evan Perez contributed to this report.