LAS VEGAS >> The abandoned baby strollers, shoes, phones, backpacks and purses strewn for days across the huge crime scene of the Las Vegas massacre were slowly being returned to their owners today to become sad souvenirs of a horrific night.

One week ago, the same scene was home to a happy day of country music for 22,000 people at the Route 91 Harvest festival. A few hours later, when 64-year-old Stephen Paddock opened fire on the crowd from the nearby Mandalay Bay hotel, killing 58 people, those thousands were left fleeing for their lives, with no care for the possessions they are now recollecting.

Federal agents have spent the week collecting evidence amid the thousands of items, some of them stained with blood.

“Whatever was dropped when people started running, those items we’re collecting and we’re going to provide back,” Paul Flood, unit chief in the FBI’s victim services division said at a news conference.

The items have been catalogued with detailed descriptions, and some have been cleaned of things including blood. They are now being returned to people at a Family Assistance Center at the Las Vegas Convention Center, starting with a few sections of the concert scene and expanding to others at a time to be announced later.

“Just in general, the sheer size of the space, the amount of personal items that were left there, it’s just a huge undertaking,” Flood said.

Also Sunday, federal investigators returned to Paddock’s southern Nevada house for what the local police chief called “re-documenting and rechecking.”

Police Chief Troy Tanner accompanied the FBI in the service of a federal search warrant at the three-bedroom house on a cul-de-sac in a retirement community in Mesquite, Nevada, Tanner told The Associated Press.

“I don’t think they are after anything specific,” Tanner said later. “They’re going through everything and photographing everything again.”

The home was searched Monday by Las Vegas police serving a warrant issued by a local judge to look for weapons and clues to Paddock’s motive.

FBI spokeswoman Sandra Breault declined to comment. Las Vegas police Officer Jacinto Rivera said he had no immediate information about the raid.

Las Vegas police have said they found 19 guns and several pounds of potentially explosive materials at the home that Paddock bought in early 2015, and where he lived with his girlfriend, Marilou Danley, who was in the Philippines during the shooting rampage.

Las Vegas hotel and gambling magnate Steve Wynn, who owns casinos that Paddock gambled in but not the Mandalay Bay, said Sunday that his hotels have undertaken special security measures in recent years to identify potentially dangerous guests. Those measures include using magnetometers to detect significant amounts of metal and training housekeeping staff to report suspicious actions like a do-not-disturb sign remaining on a door for extended periods.

Paddock spent the days before the shooting bringing bags of guns into the hotel and setting up his sniper’s perch for the shooting. He also rigged his own surveillance cameras to watch for police and hotel staff.

“If a room goes on ‘do not disturb’ for more than 12 hours, we investigate,” Wynn, whose hotels include Wynn Las Vegas and Encore told “Fox News Sunday” in an interview. “We don’t allow guns in this building unless they’re being carried by our employees, and there’s a lot of them. But if anybody’s got a gun and we find them continually, we eject them from the hotel.”

Wynn said a scenario like Paddock’s “would have triggered a whole bunch of alarms here. And we would have, on behalf of the guests, of course, investigated for safety, and it would have been a provocative situation.”

Wynn said that under a counterterrorism plan put in place in 2015, “We profile or inspect or examine everybody that enters the building.”

He added that his hotels wouldn’t invade the privacy of a guest in a room. He was quick to say that MGM Grand Resorts, which owns the Mandalay Bay, is also vigilant about safety.

Wynn said Paddock didn’t run up debts or have a gambling problem, and he had “the most vanilla profile one could possibly imagine.”

Paddock and Danley were well known to his employees, Wynn said.

“We have butlers and waiters and masseuses and the people in the beauty shop that know this woman and this man completely,” Wynn said. “They talk about normal mundane things. But if there’s anything interesting that stood out over the six years, nobody that’s ever worked here have ever seen the gentleman or the lady take a drink of wine, beer or alcohol of any kind.”

Country singer Jason Aldean, who was on stage when the shooting broke out, made a special appearance to open the telecast of “Saturday Night Live” with a performance of “I Won’t Back Down” by Tom Petty, who died in Los Angeles on Monday.

“This week we witnessed one of the worst tragedies in American history,” Aldean said before starting the song. “So many people are hurting. You can be sure that we are going to walk through these tough times together every step of the way.”

In another tribute to the 58 killed and nearly 500 injured, the casino marquees on the Las Vegas Strip will go dark at 10:05 p.m. Sunday to mark exactly a week passing since the shooting.