Terrifying First Shots in Orlando Attack Caught on Snapchat Video That Victim Sent Her Brother

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Newly revealed Snapchat video shows the heart-stopping moments that the Orlando massacre began.

A live video nursing student Amanda Alvear sent her brother from the Pulse nightclub early Sunday morning quickly goes from carefree to terrifying as deafening shots rang out.

It was the beginning of the deadliest mass shooting in modern American history.

The video begins with a clip of several people dancing at the gay bar and switches to a haunting close-up of Alvear's face as the graveness of the situation begins to take hold.

Read: How to Use a Belt to Barricade a Door During a Shooting

Tragically, Amanda was among those fatally shot by the man authorities have identified as 29-year-old Omar Mateen.

Amanda's brother Brian will likely never forget that last vision of his sister. He told Inside Edition:

"I saw the fear in her eyes immediately and it turned to dread. I just hoped that she did the right thing and escaped. But unfortunately she was in the wrong place."

Read: Orlando Gunman Pledged Allegiance to ISIS in 911 Call He Made During Attack: Report

More than a dozen shots can be heard in Amanda's video in just a few seconds.

She was among the 49 people named on Monday as deceased victims of the horrific attack. 

Mateen was also killed when he was shot by police after a 3-hour standoff. 

Watch: How The Tony Awards Honored The Victims of Orlando Nightclub Massacre