James Martin/CNET

A local election in Tennessee is dealing with the aftermath of an apparent cyberattack, and the county's mayor is calling for an investigation.

On Tuesday night, as polls were closing for Knox County's primary races for the mayoral election, the county's website displaying the results crashed. The page was down for about an hour starting around 8 p.m. local time before officials were able to restore it, according to the county's Election Commission.

"Although the crash did not affect the vote tallies or the integrity of the election, this is not something that should happen," Mayor Tim Burchett said in a statement Wednesday. "I want to know what happened, and I think an independent review will help determine that so we can move forward and work to prevent similar issues in the future."

The primary election continued, with the county announcing that Glenn Jacobs, also known as WWE wrestler Kane, won the GOP nomination by 17 votes. The crash didn't affect voting or vote tallies because the county's voting machines aren't connected online, an election official told WBIR.

Cyberattacks against elections are a major concern for the US. The Department of Homeland Security has warned against voting machine hacks and targeted attacks against campaigns. The agency said that in 2016, hackers targeted election systems in 21 states. Election officials are on high alert for future attacks.

The DHS said it's offering technical support to Knox County.

"We are aware of reports of a temporary outage affecting an election website in Knox County, Tenn. We have no information at this time that the outage was caused by a malicious actor," said Scott McConnell, a DHS spokesman.

The crash in Tennessee is a public showcase of how hackers could strike, even in a local election. Knox County IT director Dick Moran said the website's servers crashed after seeing "extremely heavy and abnormal network traffic" from IP addresses from inside and outside the US.

"Based on my experience, this was highly suggestive of a [denial of service] attack," Moran said in a statement.

DDoS attacks flood a website's servers until those computers can't handle the deluge of traffic and crash. Many cybercriminals online offer DDoS attacks as a service, some for as little as $15. It's unclear who could be behind the crash of the Knox County website.

Burchett said the county is hiring Sword & Shield Enterprise Security, a local company, to investigate the crash.

Originally published May 3 at 7:58 a.m. PT.

Update, May 4 at 6:29 a.m. PT: Adds statement from DHS.

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