TRUMP: Obama should 'resign in disgrace' since he didn't 'mention the words radical Islamic terrorism'

Presumptive Republican presidential nominee Donald Trump called on President Barack Obama to resign because he didn't use the words "radical Islamic terrorism" to describe the shooting at a nightclub in Orlando.

"Is President Obama going to finally mention the words radical Islamic terrorism?" Trump tweeted moments before Obama addressed the nation Sunday afternoon. "If he doesn't he should immediately resign in disgrace!"

In his remarks, Obama did not specifically use the words "radical Islamic terrorism." The president, however, did call the massacre an "act of terror."

A gunman killed 50 people in a gay nightclub in Orlando early Sunday. It was the deadliest shooting in US history and the deadliest terror attack on US soil since 9/11.

Omar Mateen, the suspected shooter, reportedly pledged allegiance to the terrorist group ISIS (also known as the Islamic State, ISIL, or Daesh) in a 911 call.

It was not immediately what the attacker's specific connection to ISIS was.

Business Insider has reached out to the Trump campaign for further comment.