Washington, Utah, located just southwest of Zion National Park, is surrounded by cinematic mesas and has long been a hub for exploring the natural wonders of the American west.

Yet the last 48 hours have left residents wondering how the portal to the most beautiful parts of the country may have produced one of its ugliest acts of political violence in years.

Public records and police statements indicate that Tyler Robinson, the man authorities accused of killing the conservative activist Charlie Kirk at Utah Valley University this week, resided in the area. On Saturday, authorities released an affidavit stating he was arrested on suspicion of aggravated murder, felony discharge of a firearm, and obstruction of justice.

Local and federal law enforcement descended on typically quiet blocks in Washington and nearby St George, banging on doors and closing off streets as they carried out a high stakes investigation.

Outside the home tied to Mr Robinson and his parents in Washington, neighbours expressed shock that a fellow resident could have committed such an attack.

“It shakes up a community because you don’t expect it,” said Addi Jacobson, 20, who recently moved into her grandmother’s house in the neighbourhood.

Ms Jacobson said she did not personally know the Robinson family, but her grandmother did.

“She just was saying that she thinks that, from what she’s seen and what she knows, they’re a great family, just regular citizens,” Ms Jacobson said. “She used the words, ‘very patriotic people.'”

“We knew their family. Our whole neighbourhood is so close,” said another neighbour who lived around the corner. She asked the BBC not use her name due to the heated political and online conversation around Kirk’s murder.

She recalled Tyler Robinson “was a pretty quiet kid,” though his younger brothers were more involved in community activities and sports. She called his mother, Amber Robinson, “an amazing parent,” and his father, Matthew Robinson, “a hard worker”. Both occasionally attended a nearby Mormon church, she said.

“That just even goes to show you can be an amazing parent, and your kids still just chooses what they choose,” said the neighbour.

“This is a good family,” Utah Governor Spencer Cox told CNN on Saturday. “A normal childhood. All of those things that, that you would hope would never lead to something like this. And sadly, it did.”

On 10 September, Kirk was shot in front of hundreds of students and observers, and was later pronounced dead at the hospital. Videos of the carnage spread across social media, and President Donald Trump, Vice-President JD Vance, and leaders of both major US political parties condemned the assassination.

“If you thought that my husband’s mission was powerful before, you have no idea. You have no idea what you just have unleashed across this entire country,” the activist’s wife, Erika Kirk, said in her first public statement on Saturday.

Officials initially held two suspects but later let them go. On Friday, Utah Governor Spencer Cox announced Mr Robinson was in custody. His father had persuaded him to surrender, officials said.

The night before, police vehicles descended on a townhouse complex in St George, Utah where local media reports Mr Robinson had an apartment.

Sherri Steele, who lives across the street from the residence, came back from an evening walk to see a large police presence in her complex. In a video she shared with the BBC, a loud voice – which she said belonged to authorities – can be heard shouting, “Freeze!” and “Come out now!”

“It just kind of blows your mind, coming up the street and all the sudden there are helicopters above your house,” Ms Steele said, adding she had never spoken or interacted with Mr Robinson.

Another neighbour, 18-year-old Josh Kemp, said he had seen Mr Robinson leaving his house on one occasion with a roommate.

According to Mr Robinson’s affidavit, police interviewed a roommate who showed them messages Robinson had allegedly posted on Discord.

The messages, attributed to Mr Robinson, discussed a “need to retrieve a rifle from a drop point, leaving the rifle in a bush, messages related to visually watching the area where a rifle was left, and a message referring to having left the rifle wrapped in a towel.”

“The messages also refer to engraving bullets, and a mention of a scope and the rifle being unique,” the affidavit states.

Utah County Attorney Jeff Gray plans to file formal charges against Mr Robinson on Tuesday, CBS News reported, and the accused will have his first court appearance that day.

The nation – including the current occupants of the White House in Washington, DC – will be watching.

But Washington, Utah will too.

“This whole time, I never knew that I was living next to somebody capable of something like this,” Ms Jacobson said as she played in the park with her fiancé and baby.

“It just makes you kind of question: how much closer am I to somebody else that could be this way?”