Watch a New Doc on One of the Deadliest U.S. Attacks on LGBT People

ABC News Features has released a digital documentary on one of the worst mass killings of LGBT people.

Prejudice and Pride, a 30-minute film, was posted online Thursday in advance of the 45th anniversary of the fire at the UpStairs Lounge, a New Orleans gay bar where an arsonist killed 32 people and injured many others on June 24, 1973. Until the Pulse masscare in 2016, it was the deadliest attack on the queer community in U.S. history.

Drawing from Robert W. Fieseler's book Tinderbox: The Untold Story, of the UpStairs Lounge Fire and the Rise of Gay Liberation, the documentary includes interviews with survivors, family members of the dead, journalists, and community leaders to tell the story of this tragic event, which for decades remained largely untold due to homophobia.

In recent years, the fire at the UpStairs Lounge has inspired two musicals, UpStairs and The View UpStairs; another documentary film, UpStairs Inferno; and an award-winning 2013 article in The Advocate magazine by Diane Anderson-Minshall.

"Everybody's so outraged about it now," said interview subject Duane Mitchell, who was 11 when his father died in the blaze. "Where were they then? Nobody wanted to talk about it. It was like my dad and all those other people never existed."

ABC News Features also follows the family of a World War II veteran who was a victim of the fire. The man was buried in an unmarked grave, and his loved ones are now searching for his remains.

Watch the documentary below.