An online fundraising campaign for victims of the Las Vegas shooting has raised more than $2.5 million.

The GoFundMe page goal was initially $2 million (and later increased to $3.5 million late Monday night) -- and donations started to pour in after Steve Sisolak, chairman of the Clark County, Nevada, Board of County Commissioners, which includes Las Vegas, started the fund Monday. Donors contributed more than $2.9 million as of 6 a.m. EDT on October 3.

"I'm overwhelmed by the outpouring of support from the Las Vegas community & beyond. We need more donations, every penny will be put to use," Sisolak said in a post on Twitter.

I'm overwhelmed by the outpouring of support from the Las Vegas community & beyond. We need more donations, every penny will be put to use. — Steve Sisolak (@SteveSisolak) October 2, 2017

Sisolak, who said he started the fund with Clark County Sheriff Joseph Lombardo, pledged the first $10,000, he said on Twitter.

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Las Vegas, in Clark County, is governed by a seven-member County Commission that is elected from geographic districts on a partisan basis for staggered four-year terms, according to the website.

A gunman perched on the 32nd floor of a Las Vegas Strip casino unleashed a shower of bullets down on an outdoor country music festival below, killing at least 58 people and wounding more than 527 as thousands of frantic concert-goers screamed and ran for their lives, Lombardo said Monday.

It is the deadliest mass shooting in modern U.S. history.