A fun night of music on the Las Vegas Strip became the scene of one of the most horrific mass shootings in U.S. history.
In the end, 59 people were dead and 527 people were hurt either by being shot or in the scramble to get away.
People take cover at the Route 91 Harvest festival after a gunman opened fire on the festival from a room in the Mandalay Bay Resort and Casino in Las Vegas.
A cowboy hat lies in the street in Las Vegas. The Route 91 Harvest music festival ended in violence and chaos as thousands of people sought to escape an attack from above that they couldn't see.
An unidentified woman sits on the curb after the massacre of country music fans at a concert on the Las Vegas Strip.
Windows broken out by the gunman on the 32nd floor of the Mandalay Bay hotel-casino.
Thousands of Las Vegas line up to donate blood in the wake of Sunday's massacre. The line at the United Blood Services office on Charleston wrapped around the block.
It wasn't just blood but people also donated water to the lines of people standing outside to give blood.
Thousands lined up outside United Blood Services on West Charleston Blvd. to donate blood.
Red Cross volunteers moved donated items into the Family Assistance Center set up at the Las Vegas Convention Center.
Florists in Las Vegas for a wedding convention use their flowers to create a display for the families of victims and survivors.
The window smashed out by the shooter on the 32nd floor of Mandalay Bay.
Police tape surrounds a portion of Mandalay Bay hotel-casino, while police continue their investigation of the shooting scene.
Metro Police cars parked outside one of the four crime scenes police are processing.
Attendees of a vigil at Las Vegas City Hall light candles.
Mourners at a vigil at Las Vegas City Hall.
Mourners gather at Las Vegas City Hall Monday night.
Clark County Commission Chairman Steve Sisolak speaks at a vigil at Guardian Angel Catholic Church on Las Vegas Blvd.
Mourners gather at Guardian Angel Catholic Church on Las Vegas Boulevard Monday night.
MGM Resorts International CEO Jim Murren embraces an employee outside a vigil Monday night.
MGM Resorts International CEO Jim Murren talks with a employee after a vigil Monday night.