Late on the evening of October 1st, Stephen Paddock, aged 64, opened fire on an outdoor concert on the Las Vegas Strip. The worst mass shooting in American modern history occurred at the Route 91 Harvest Festival, during Jason Aldean’s set. Paddock, a resident of Mesquite, Nevada, rained down a barrage of fire on the unsuspecting crowd from his hotel room on the 32nd floor of the Mandalay Bay Resort and Casino.

The incident left at least 58 people dead and 400 injured, and many more scrambling for cover. As bullets sprayed across the venue from a room filled with weapons, concertgoers fled, running for their lives. Those injured were treated by EMT’s, police officers, and even bystanders who had the courage to help the wounded through the gunfire. Melissa Ayala, 41, came to the country music festival with four friends from Orange, California. They were drinking and laughing when they heard what they thought was fireworks. She did not realize it was gunfire until a man near them was grazed by a bullet and fell to the ground, blood coming from his neck, according to the New York Times. “It seemed like rapid fire,” she said. “There was blood pouring everywhere.”

In the hotel room where the fire was coming from, Paddock had stockpiled 23 weapons. Back in his Mesquite home, he had at least 18 additional guns, multiple explosives, and thousands of rounds of ammunitions, BuzzFeed reports. He had also recently bought several weapons, three from his local gun shop, Guns and Guitars, within the last year, according to the New York Times. All three of the gun purchases were legal. “The man does not have a criminal history,” Mr. Sullivan, the manager of Guns and Guitars, said of Mr. Paddock.

During the attack, Paddock fired at officers who tried to break into his room. When SWAT teams were finally able to enter, however, he was deceased. “We believe the individual killed himself prior to our entry,” said Clark County Sheriff Joe Lombardo, CNN reports.

Following the shooting and the subsequent death of the shooter, ISIS claimed responsibility for the attack. They stated that the gunman was “a Soldier of the Islamic State,” No evidence was provided for its claim, though. The group said that Paddock was a recent convert to Islam, and carried out the attack. However, in recent times, the group has made at least two false claims, including for an attack on a casino in Manila and a bomb plot at Charles de Gaulle Airport in Paris, NYTimes reports.

The incident shocked many Americans. Americans, however, are tough. People all over the country have rallied behind Las Vegas by raising money, donating blood, and sharing information, all to help victims of the tragedy. If you would like to donate blood, please contact the American Red Cross for information.