https://c-8oqtgrjgwu46x24koi-u-oup-eqox2ecmcockbgfx2epgv.g00.msn.com/g00/3_c-8yyy.oup.eqo_/c-8OQTGRJGWU46x24jvvrux3ax2fx2fkoi-u-oup-eqo.cmcockbgf.pgvx2fvgpcpvx2fcorx2fgpvkvakfx2fCCw5CMV.koix3fjx3d980x26yx3d3588x26ox3d8x26sx3d82x26qx3dhx26nx3dhx26k32e.octm.kocig.varg_$/$/$/$/$
LOS ANGELES — Determining a motive for the man who committed one of the deadliest mass shootings in modern history continues to be an exasperating task for investigators. They have interviewed many of Stephen Paddock’s relatives and friends, and examined his travel, financial and health history. But they have yet to find anything that points to what drove him to kill 58 people at a concert in Las Vegas on Oct. 1.
On Wednesday, information emerged that adds to the complexity of the case. Mr. Paddock apparently removed the hard drive from at least one computer found in his room at the Mandalay Bay Resort and Casino, according to a law enforcement official.
Additionally, housekeepers had visited Mr. Paddock’s room, where he fired on the crowd below, more than once in the days before the shooting, but did not notice any sign of his large stockpile of weapons. He also ordered room service at least once, according to people with knowledge of the security response inside the hotel.
Separately on Wednesday, Mr. Paddock’s brother was arrested at an assisted living facility in Los Angeles on charges of possessing child pornography.
Mr. Paddock’s activities at the hotel have been carefully tracked. He was a “lifetime winner” at MGM Resorts properties, which include Mandalay Bay. The term refers to gamblers who have won more money than they have lost over the years, raising doubts about whether Mr. Paddock had any grievance against the hotel. He also gambled during his stay the weekend of the shooting.
Over the last year, Mr. Paddock traveled widely to buy his large cache of guns — more than two dozen were discovered in his room and more were at his home in nearby Henderson, Nev. Investigators have said the weapons were purchased legally and gun store owners said they saw no warning signs from Mr. Paddock.
Suspects in mass shootings typically leave long trails of clues to justify their actions, writing manifestoes or posting on social media. But Mr. Paddock did not appear to do so, leaving investigators from the Federal Bureau of Investigation to pore over his computers and cellphones in the bureau’s lab in Quantico, Va., for weeks.
Examining suspects’ computers and phones has become an essential part of criminal investigations, allowing law enforcement officials to retrace their steps, track their communications and identify their motives and possible accomplices. ABC News first reported that Mr. Paddock’s hard drive was missing from a computer on Wednesday.
After the massacre last year at a nightclub in Orlando, the electronic trail left by the gunman, Omar Mateen, who declared allegiance to the Islamic State during the attack and then killed himself, helped establish how he had become radicalized and planned for the attack. The government has cited that evidence in the pending criminal case against his widow, Noor Salman, who prosecutors contend knew of his plans and lied to investigators after the killings.
The search for electronic evidence has led in unexpected directions, sometimes entangling people who were not directly involved in the crimes. After the Boston Marathon bombing, friends of one of the bombers were convicted and sent to prison for discarding his laptop and other evidence to keep it from investigators, and for lying to federal agents about it.
After a mass shooting in San Bernardino, Calif., in 2015, the F.B.I. said that it was crucial for agents to examine the iPhone used by one of the suspects, and tried to force Apple to help the bureau unlock the device. Eventually, the F.B.I. said it was able to retrieve data from the phone without Apple’s help.
Mr. Paddock’s brother Bruce Douglas Paddock, 59, was arrested Wednesday morning by detectives from a task force led by the Los Angeles Police Department to combat child pornography. Investigators have interviewed many of Stephen Paddock’s relatives and it is unclear whether the brothers had been in contact. A police spokesman said it was entirely a coincidence that Bruce Paddock was arrested less than a month after the shooting, adding that the investigation had been going on for months.
Police began the inquiry several months ago after Bruce Paddock, who is homeless, was evicted from a business where he had been squatting. He was charged with possession of more than 600 images of child pornography and 19 counts of sexual exploitation of a child. He is being held on a $60,000 bail.