The lighting up took place as the sun set and was followed by a vigil in Hurst Street, at the heart of Birmingham’s Gay Quarter.
Almost 50 people were killed and another 53 were enjured after a heavily-armed gunman released fire at Pulse, a gay nightclub in Orlando, Florida.
The rainbow flag is a symbol for the LGBT (Lesbian, Gay, Bisexual and Transgender community).
The Library of Birmingham has previously lit up in light of the Brussels and Paris attacks.
![Library of Birmingham pays tribute to the Paris attack victims](http://www.theasiantoday.com/wp-content/uploads/2016/06/Library-of-Birmingham-pays-tribute-to-the-Paris-attack-victims.jpg)