WASHINGTON (CBSNewYork/AP) — President Donald Trump called a deadly mass shooting in Las Vegas that left at least 59 people dead and more than 500 others hurt “an act of pure evil.”

Speaking Monday from the White House, the president said “we are joined together today in sadness, shock and grief.” He said in “moments of tragedy and horror, America comes together as one.”

PHOTOS: Las Vegas Concert Shooting

“I know we are searching for some kind of meaning in the chaos, some kind of light in the darkness. The answers do not come easy,” Trump said. “We pray for the day when evil is banished and the innocent are safe from hatred and from fear.”

The president also praised first responders, saying their speed “prevented further loss of life.”

“To have found the shooter so quickly after the first shots were fired is something for which we will always be thankful and grateful,” he said.

Trump said he and first lady Melania Trump are praying for those who have been lost and wounded. He said they are praying “for the entire nation to find unity and peace.”

He also ordered flags to be flown at half-staff in honor of those killed.

The president said he would be visiting Las Vegas Wednesday to meet with law enforcement, first responders and families of the vitcims.

In a tweet earlier Monday, Trump offered “My warmest condolences and sympathies to the victims and families of the terrible Las Vegas shooting. God bless you!”

My warmest condolences and sympathies to the victims and families of the terrible Las Vegas shooting. God bless you! — Donald J. Trump (@realDonaldTrump) October 2, 2017

Police said a gunman, identified as 64-year-old Stephen Paddock, opened fire Sunday night at a country music concert festival.

Authorities said they believe the incident, now the deadliest mass shooting in modern U.S. history, was a “lone wolf” attack.

(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)