Updated at 11:47 a.m. ET

President Trump solemnly addressed the nation Monday morning about Sunday night's mass shooting in Las Vegas, saying Americans are "joining together in sadness, shock and grief."

In brief remarks from the White House Diplomatic Reception Room, Trump called the shooting, in which police say at least 58 people were killed and over 500 were wounded, "an act of pure evil." He said he will visit Las Vegas on Wednesday, and he ordered flags flown at half-staff.

Trump praised first responders, including the Las Vegas Metropolitan Police Department, "for their courageous efforts." He said the speed with which they reacted to the shooting was "miraculous and prevented further loss of life." Trump noted that the FBI and Department of Homeland Security are working with local authorities on the investigation.

Trump said of the victims, most of whom were attending a country music concert, "We cannot fathom their pain; we cannot imagine their loss." The president quoted from Scripture that "the Lord is close to the brokenhearted," and said he and first lady Melania Trump are praying for the speedy recovery of the wounded and for the families of the victims.

"In moments of tragedy and horror," Trump said, the nation "comes together as one." He continued, "Our unity cannot be shattered by evil; our bonds cannot be broken by violence."

Trump had been briefed earlier in the morning on the attack and tweeted, "My warmest condolences and sympathies to the victims and families of the terrible Las Vegas shooting. God bless you!"

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