LAS VEGAS (WLS) -- Las Vegas police said Stephen Paddock had a plan to escape following Sunday's mass shooting. They also said he left a note in his room. While they declined to disclose what it said, they confirmed it was not a suicide note."Stephen Paddock is a man who spent decades acquiring weapons and ammo and living a secret life, much of which will never be fully understood, and planned on the worst massive attack," said Las Vegas Sheriff Joe Lombardo at a Wednesday evening press conference.Lombardo said Paddock had an escape plan, a scheme that may have included containers of explosive chemicals found in his car.Authorities also now say Paddock, 64, must have had some help at some point; they just don't know who, or why.The gunfire rained down on the crowd long enough to kill 58 people and wound hundreds. Las Vegas authorities said Wednesday night the first police officers arrived on the shooter's floor 12 minutes into the incident, and their timeline shows a police SWAT team blew down his door at Mandalay Bay Hotel and Casino 75 minutes after the first shots.They cited a hero hotel security guard who, unarmed, was responding to initial noise complaints and found the shooter's door ajar. He was shot through the door."His bravery was amazing because he remained with our officers, providing them the key pass to access the door, and continued to help them clear rooms until our officer demanded he seek medical attention," Lombardo said.In Los Angeles, the FBI questioned Paddock's girlfriend Marilou Danley. He had sent Danley to the Philippines, according to her sisters to be far away at the time of the attack. Danley, considered a "person of interest" by police, has an attorney at her side."How could she not know what was going on in her own house with these weapons? She had to know something, at the very least question him as to where are these weapons coming from, why do you have all these weapons," said Steve Gomez, a former FBI counterterrorism official.Her attorney read a statement on her behalf Tuesday afternoon, saying in part, "He wanted me to take a trip home to see family. While there, he wired me money which he said was for me to buy a house for me and my family. I was grateful, but honestly, I was worried at first the unexpected trip home and then the money was a way of breaking up with me. It never occurred to in any way whatsoever he was planning violence against anyone."President Donald Trump arrived in Las Vegas Wednesday morning to meet with first responders and some survivors."So I just want to congratulate everybody. It's incredible," Trump said while visiting a hospital.Trump praised emergency responders after visiting some of the wounded who are still hospitalized. Trump complimented law enforcement for bravely ending the shooting spree before it got any worse, even though investigators are still working to answer the question of what motivated such a deadly one-man battle plan by 64-year-old Stephen Paddock."I can tell you it's a very sick man and he was a very demented person," Trump said.The local sheriff now says investigators have "a couple good leads" in determining what led to the Sunday night massacre.They have determined Paddock purchased 33 rifles in four different states.A memorial tribute is growing just down the street from the Mandalay Bay Hotel and Casino. West suburban St. Charles native Darlene Watson was among the mourners who visited it."It's really sad, it's a tragedy," she said."Many families will go to bed tonight in a world that is now empty. Our souls are stricken with grief. We stand together to help you carry your pain. We will never leave your side," Trump said.The FBI and Las Vegas police are looking into whether a concert by Chicago's Chance the Rapper was Paddock's original target.Chance performed last month in Las Vegas at an outdoor venue similar to where Paddock killed 58 people on Sunday from a sniper's perch on the 32nd floor of the Mandalay Bay resort.Now, investigators are looking into whether Paddock tried to get a room in a high-rise building overlooking the Sept. 22 "Life is Beautiful" concert, which featured Chance and Lorde, similar to the perch he fired from at Mandalay Bay on Sunday night.Authorities have not said whether that concert last month was an active target that went awry or a scouting mission. Las Vegas police confirm the alternate attack possibility is part of their ongoing investigation.When SWAT officers raided Paddock's room at the Mandalay, where thousands of rounds were fired on a Jason Aldean country concert, Paddock was alone.