Matthew Livelsberger – the driver of the Tesla Cybertruck that exploded outside the Trump International Las Vegas Hotel on New Year’s Day – shared personal and political “grievances” in two letters found on a phone in the vehicle, calling the attack a “wake-up call.” . call,” authorities said Friday.

Livelsberger, an active-duty soldier, said the country was run by the “weak” and those who wanted to “enrich themselves,” while maintaining that the incident was not intended as a terrorist attack, as excerpts the two shared Letters from the Las Vegas Metropolitan Police Department.

“I know everyone is very interested in understanding and being able to explain what happened,” Las Vegas Sheriff’s Deputy Dori Koren said during a news conference Friday. “We still have large amounts of data and a lot of content to sift through.”

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The department released the two letters to the public after the press conference.

“You’ll see that in one of these documents that we’re going to release to you, he actually calls it a stunt, that he was trying to get the attention of the American people because he was upset about various things,” Sheriff said Kevin McMahill of the Las Vegas Metropolitan Police Department during Friday’s briefing when asked about the suspect’s political views. “But I’ll let these writings speak for themselves.”

In one of the letters that police said were found on his phone, Livelsberger expressed support for Donald Trump and the president-elect’s allies, Elon Musk and Robert F. Kennedy Jr. According to the letters, he expressed concern about homelessness.

Livelsberger died of a self-inflicted gunshot wound before the explosion, the Clark County coroner confirmed Thursday evening. No one else was seriously injured, although seven bystanders suffered minor injuries, officials said.

The evidence shows Livelsberger was “carefully prepared” and acted alone in the incident, said Spencer Evans, special agent in charge of the FBI’s Las Vegas Division, during Friday’s news conference. Livelsberger was not on the FBI’s radar before the incident, Evans said.

“Although this incident is more public and high-profile than usual, it ultimately appears to be a tragic suicide case involving a decorated combat veteran who was struggling with post-traumatic stress disorder and other issues,” Evans said.

Authorities are also investigating a letter allegedly sent by Livelsberger that was published on the military-themed podcast “Shawn Ryan Show” on Friday. This information was forwarded to the FBI after the attack, Evans confirmed.

“We still have not conclusively determined that this came from the individual, but are confident that this is indeed from Livelsberger based on the evidence we are discovering on his devices,” Evans said.

Inside the Cybertruck, officers found credit and ID cards in Livelsberger’s name, evidence that he owned the weapons found in the wrecked vehicle, and identified tattoos that appeared to match Livelsberger’s body. However, serious physical injuries slowed the identification process.

The Clark County coroner on Thursday finally identified Livelsberger, of Colorado Springs, Colo., as the driver. His cause of death was a self-inflicted intraoral gunshot wound.

Livelsberger was found with a gun at his feet. Two firearms – a pistol and a rifle – were found “burned beyond recognition” in the vehicle, McMahill said.

Both weapons were purchased legally on Monday, he added.

Two phones were recovered from the vehicle, including one containing the two letters, Koren said. At that point, investigators were unable to access the other phone, he said.

It is unclear why Livelsberger chose a Tesla or what route he took, authorities said Friday.

Livelsberger rented the Tesla vehicle in Denver on Saturday through the Turo app before driving through cities in Colorado, New Mexico and Arizona to Las Vegas. His progress was tracked through Tesla charging stations, officials said.

The vehicle first pulled into the valet parking at the Trump International Las Vegas Hotel just after 7:30 a.m. Wednesday, officials said. It then left the area and traveled down Las Vegas Boulevard before returning to the valet area at around 8:39 a.m. and exploding 17 seconds after arriving.

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Livelsberger served as a Green Beret in the Army and was on approved leave from duty in Germany at the time of his death, a U.S. Army spokesman said Thursday.

He received extensive decorations in combat, including the Bronze Star with a “V” for valor, indicating heroism under fire. According to Army records, Livelsberger received four additional Standard Bronze Star medals. He also received the Afghanistan Campaign Medal with three stars. Each star represents deployment in a separate campaign in Afghanistan.

Livelsberger received psychological help last year, a U.S. official confirmed Friday.

Another US official confirmed that Livelsberger was deemed stable enough to go home for Christmas and his leave was approved.

The Defense Department has turned over Livelsberger’s medical records to local law enforcement, Pentagon press secretary Sabrina Singh told reporters during a briefing Friday.

“I just don’t have any other details to share,” she added when asked about CNN’s reporting that the suspect was diagnosed with depression last year.

Singh noted that service members are encouraged to seek help for mental health issues.

The Las Vegas incident is not believed to be directly related to the New Year’s Day truck attack in New Orleans that killed 14 people – as well as the suspect – and injured 35 others, according to the FBI. The truck used in the New Orleans attack was also rented through the Turo app, officials said.

Evans reiterated Friday that there was no evidence that the two events were related, saying there were “coincidental similarities” between them – including that both drivers were in the military, rented vehicles through the same service and stayed in an Airbnb.

There is currently no evidence that there was any overlap between the two drivers, although both served in Afghanistan, Singh also said on Friday.

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Livelsberger was a supporter of Trump, an official briefed on the investigation told ABC News. His wife, whom investigators spoke to in Colorado Springs, said he had been out of the house since around Christmas after an argument over infidelity allegations, the official said.

His wife told officers she didn’t think Livelsberger wanted to hurt anyone, the officer told ABC News.

Livelsberger allegedly told the person he rented the truck from that he wanted to camp at the Grand Canyon, the official told ABC News.

Investigators are still trying to determine how the items in the truck were detonated, but because the vehicle’s contents were so badly burned, it could be a slow process, according to the official.

The sheriff said Tesla CEO Musk assisted the investigation by having the truck unlocked after it automatically locked itself when it exploded and by providing investigators with video of the suspect at charging stations on his route from Colorado Las Vegas provided.

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McMahill said police believe the explosion was an “isolated incident” and that “there is no further threat to the community.”

Video at Thursday’s news conference in Las Vegas showed a load of firework-like mortars, gas cans and camping fuel cans in the back of the truck.

If you are struggling with suicidal thoughts or are worried about a friend or loved one, call or text Suicide & Crisis Lifeline on 988 for free, confidential emotional help 24 hours a day, seven days a week to receive support.

Las Vegas Cybertruck explosion: 2 letters found on suspect’s phone, police say originally appeared on abcnews.go.com