By Cassandra Santiago and Brandon Griggs, CNN

(CNN) -- The cards and letters, filled with messages of sympathy and hope, pour in from around the world.

Addressed to Las Vegas City Hall, they offer heartfelt condolences over the October 1 mass shooting that left 58 dead, nearly 500 injured and psychic scars across the Nevada desert city.

The flood of mail started after the city's social media team launched Hearts4Vegas, a campaign for people looking for ways to help Las Vegas heal.

"They wanted to try to help Las Vegas in some way," Jace Radke, a senior public information officer for the city, told CNN. "They wanted to do something."

Hundreds of cards and letters have arrived in recent days, both through the mail and dropped into an aqua blue box sitting outside City Hall. Adorning the box is an image of nine red balloon hearts against a white circle, above the phrase, "Hearts 4 Vegas."

City officials don't know when they will stop accepting letters, said Radke, but they are discussing options for where and how to display them in the community.

The campaign isn't the only way residents and others contributed to the city after the shooting.

Hundreds stood in lines for up to eight hours to donate blood. A retired carpenter drove from Illinois to Las Vegas to donate 58 handmade wooden crosses in honor of the victims. Clark County Commission Chairman Steve Sisolak started a GoFundMe page that has raised more than $10 million in donations for victims' families.

Others opened their homes for victims' families and friends, while local restaurants donated food to officials working on the criminal investigation, Radke said.

With help from hundreds of volunteers, Stonerose Landscapes in nearby Henderson led the construction of a healing garden on an empty plot of city land downtown. More than 2,000 people showed up at the garden for a dedication ceremony, Radke said.

The-CNN-Wire

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