Tonight with video, you haven't seen before pictures of a hero taking a mass murder

is gone away, confronting, grappling with him and disarming someone who had just moments

before shot in fendally wounded 11 people at another location and was about to do the

same.

Again, Saturday night at a ballroom in Dan's studio in Alhambra, California just outside

Los Angeles, the Brandon Sain, his family, run.

The video is slowed down somewhat.

The man in the frame is the 72 year old mass killer who had already carried out a mass

shooting at another ballroom in nearby Monterey Park.

Now, the weapon he's carrying, according to authorities, is a 9 mm Ingram Mac 10 semi-automatic

with what appears to be a suppressor or silencer which authorities say he'd been making at home.

Brandon Sainte tells us he heard sounds, metal on metal noises, and you can see the shooter

pulling back on the weapon.

And then for a few seconds, he withdraws into the doorway as if to look around at which

point seconds later, he sees Brandon there entering and confronting the man.

His arms outstretched, reaching for the man and then the weapon.

The struggle then moves into the doorway and just outside that room.

We're just seeing this for the first time.

You've never seen this video before.

Brandon will describe in a moment just what was happening, what he was doing and thinking

in the seconds that we see and what we don't see.

Again, the killer has a Mac 10, apparently a suppressor and stock.

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