orlando shooting
orlando shootingReuters

Law enforcement sources have reportedly said the wife of Omar Mateen, the gunman who killed 50 people and injured another 53 in an attack on a gay nightclub in Orlando, knew of her husband's plans and could soon face charges.

A Fox News report said Noor Salman, the gunman's wife, told the investigators Mateen had shared with her his plan to attack the nightclub, and may have even called her during the attack.

According to Reuters, federal prosecutors had convened a grand jury and could charge Salman on Wednesday. They seek to charge her as an accessory to 49 counts of murder and 53 counts of attempted murder. She will also be charge for failing to notify law enforcement about the attack and lying to federal agents.

"It appears she has some knowledge of what was going on, visiting some of the other sites. We don't know whether she was involved and knew about the purchase of the guns, which took place only about a week before the attack... But she definitely is, I guess you would say, a person of interest right now and appears to be cooperating and can provide us with some important information on who this guy is, what his motivations were and what his plans were," U.S. Senator Angus King, a member of the Senate Intelligence Committee, was quoted by CNN as saying.

According to a report by NBC News, a federal law enforcement source said Salman tried to dissuade Mateen from carrying out the attack, but then drove him to the Pulse nightclub once because he wanted to check it out. She was also with him when he bought weapons for the attack.

Salman has been cooperating with investigators and has also taken a polygraph test, a CBS News report stated. She had also scouted Downtown Disney in April and in early June as an alternate location to carry out the attack.

Reuters quoted Mateen's ex-wife as saying he was mentally unstable and physically abused her. She reportedly ran away from their house four months after the marriage.

Rajinder Chahal, a neighbour of Salman's mother Ekbal Zahi Salman, who lives in Rodeo, California, said she visited her daughter only once and that she "didn't like him (Mateen) very much. He didn't allow her (Noor) to come here." The agency quoted Chahal as saying that "she was crying, weeping" when he spoke to her about the Sunday attack.