President Calls Orlando Murders Attack on All Americans

President Barack Obama on Sunday described the worst mass shooting in U.S. history as "an act of terror" and "an act of hate," saying the massacre of 50 people at a packed gay nightclub in Orlando, Florida was an attack on all Americans.

"Today as Americans we grieve the brutal murder, a horrific massacre of dozens of innocent people," he said in a statement at the White House. 

"Although it is still early in the investigation, we know enough to say that this was an act of terror and an act of hate," Obama said.

"We will not give in to fear or turn against each other. Instead, we will stand united as Americans to protect our people and defend our nation, and to take action against those who threaten us."

He ordered the flag at the White House to be flown at half staff to honor the victims. 

The shooter, who was identified as Florida resident Omar S. Mateen was killed by police at the nightclub. A top U.S. congressman said Mateen may have pledged allegiance to the Islamic State militant group, but U.S. officials cautioned they had no direct evidence of a connection. 

Fifty-three people were wounded in the rampage, which surpassed the 32 people killed in the 2007 massacre at Virginia Tech university.