12:05 PM PT -- An MGM Resorts spokesperson also tells us:

“The tragic incident that took place on October 1st was a meticulously planned, evil senseless act. As our company and city work through the healing process, our primary focus and concern is taking actions to support the victims and their families, our guests and employees and cooperating with law enforcement ... Out of respect for the victims we are not going to try this case in the public domain and we will give our response through the appropriate legal channels.”

12:00 PM PT-- A rep for Live Nation tells us, "We continue to be devastated by the tragedy at the Route 91 Festival, heartbroken for the victims, their families and the countless people forever impacted by this senseless act of violence and are cooperating fully with the active FBI investigation. We are, however, unable to comment specifically on pending litigation."

One of the Las Vegas shooting victims has filed the first lawsuit against Stephen Paddock's estate along with MGM Resorts and Live Nation, claiming they're all to blame for her life-threatening injuries.

Paige Gasper, a 21-year-old from CA, filed the suit in Clark County, Nevada ... and in the docs she says the venue and promoter are just as responsible as Paddock because they failed to properly protect concertgoers from mortal danger.

Gasper says she was struck by a bullet that entered her right underarm, cut across her right breast, shattered her ribs and lacerated her liver before exiting her body. She says the bullet incapacitated her, and fleeing concertgoers ended up trampling her, which she partly blames on Live Nation for having an inadequate exit plan.

A Good Samaritan eventually picked her up and put her on a flatbed truck with other victims, and they were raced to a hospital. Gasper is also suing the manufacturers of bump stocks, which helped turn Paddock's semi-automatic rifle into a near fully-automatic weapon.

We've reached out to MGM and Live Nation, so far no word back.