Oct. 3 (UPI) -- Investigators said Stephen Paddock, the man who killed at least 59 people at a Las Vegas country music festival, set up a series of cameras in and outside of his hotel room to monitor police.
Las Vegas Metropolitan Police Department Sheriff Joseph Lombardo said evidence discovered in Paddock's suite on the 32nd floor of the Mandalay Bay Resort and Casino suggests he planned the attack.
"It was pre-planned, extensively, and I'm pretty sure that he evaluated everything that he did in his actions, which is troublesome," Lombardo said during a Tuesday afternoon briefing.
Lombardo said Paddock installed cameras inside his room and at least one hidden in a room service cart outside his hotel room door, so he was able to see police when they approached his door.
The sheriff said Paddock shot one hotel security guard who had become separated from police through the hotel room door. He was injured in the leg.
After that point, police broke inside the room to find Paddock had killed himself.
Officials said 59 people died and 527 were injured after Paddock fired on a crowd at the concert across the street from the hotel Sunday night. More than 104 of the injured were admitted to University Medical Center, where 12 were in critical condition. Sunrise Hospital and Medical Center took in 214, and St. Rose Dominican's three area hospitals treated 61 people.
Lombardo warned the death toll could rise.
"We are notifying next of kin and working with Emergency Services personnel and Las Vegas Metro police to provide information to families trying to locate loved ones who may be in our care," St. Rose Dominican spokeswoman Stacy Acquista said.
Las Vegas Boulevard, typically a hotspot for lively activity, has taken on a more somber mood in the wake of the shootings.
The city's restaurants brought free food to police stations, hospital emergency rooms and to those waiting in long lines to donate blood. Churches held vigils and services. Support for Las Vegas could be seen as far away as Paris, which dimmed the lights on the Eiffel Tower in tribute. On orders of President Donald Trump on Monday, flags across the United States flew at half-staff.
Authorities said 22 rifles and a handgun were found in Paddock's hotel room and another 18 rifles were discovered at his Mesquite home.
Citing a police source, WFXT-TV, Boston, displayed photographs on Tuesday of two of the weapons it said were found in Paddock's hotel room. The photograph showed ammunition casings littering the floor.
Lombardo said that ammonium nitrate, a bomb-making material, was found in Paddock's car at the hotel. Officials said a search warrant was executed at another home Paddock owned in Reno.
While there remained more questions than answers in the incident, Las Vegas residents showed little bitterness, and found ways to contribute in serving their city. Some blood donation centers reported an eight-hour wait and Clark County Commissioner Steve Sisolak reported that on online campaign to secure donations for victims and their families topped $2.5 million by mid-day.
Candlelight vigils were also held around the city on sections of the Strip.
The motive for the attack has not been established. Investigators said Paddock, a twice-divorced retiree with an interest in gambling and real estate transactions, had no criminal history and did not leave a letter of explanation his actions. Police said he killed himself as police entered his hotel room, ending the massacre.
Several of the theaters along Las Vegas' famed Strip of hotels and casinos remained open, offering free entertainment.
David Saxe of the V Theater and Saxe Theater complex told the Las Vegas Review-Journal, "Sometimes, when people don't know what to do, they want to get away from it for a couple of hours. This is not about the money. It's just if you want to see a show, we'll have a show."