The top U.N. human rights official on Monday condemned the deadly attack by a gunman targeting people at a homosexual bar in Orlando, Florida.

A man armed with an assault rifle and pledging loyalty to Islamic State killed 50 people during a gay pride celebration at a nightclub in Orlando, Florida, early on Sunday in the deadliest mass shooting in U.S. history.

"I also condemn with the greatest possible force the outrageous attacks by violent extremists on innocent people, chosen at random, or because of their presumed beliefs, or opinions, or - as we saw yesterday - their sexual orientation," Zeid Ra'ad al Hussein told the start of a three-week session of the U.N. Human Rights Council in Geneva.