It was not the Black Friday headline Best Buy was hoping for.

The Richfield-based electronics chain stumbled on one of the biggest shopping days of the year with its website going down twice in one day.

Best Buy attributed the issue to "record levels of website traffic" that overwhelmed its site.

"A concentrated spike in mobile traffic triggered issues that led us to shut down in order to take proactive measures to restore full performance," the company said in a statement.

The first hiccup was around 9 a.m. and lasted about an hour before the website was back online. Then it happened again around 4:30 p.m. and also lasted about an hour.

When shoppers went to the website during those times, they were greeted by a picture of a wreath with the message: "We're sorry. is currently unavailable. Check back soon."

Jeff Shelman, a Best Buy spokesman, said the issue was not related to a cyberattack.

While the timing was obviously unfortunate, it shouldn't be a significant blow to the company, said Stephen Baker, an analyst with the NPD Group.

"It wasn't like it was down the whole day," he said shortly after Best Buy took down the site the first time. "It was an hour. It's hard to see that will cause any appreciable blow in its performance."

But still, it was an inopportune misstep with online sales taking on an increasingly large role in holiday shopping. The firm ComScore expects online sales to grow 16 percent during this holiday season.

Target said it set a company record for online sales on Thanksgiving Day. Wal-Mart said that day was its second-biggest online day, behind only last year's Cyber Monday.

Best Buy would not provide any information about its level of online sales on Thanksgiving or Black Friday other than nodding to the record level of traffic on Friday.

IBM Digital Analytics Benchmark said online sales as of Friday evening rose 8.5 percent on Black Friday, compared to the previous year, with nearly half of the traffic coming from mobile devices. It said online sales were up 14.3 percent on Thanksgiving.

But Best Buy wasn't the only retailer who has struggled with its website in recent days. A Kohl's spokeswoman confirmed that some customers had trouble accessing its site on Wednesday "for a short period of time" because of an issue with its third party technology provider.

And Topshop's website was also down for some time on Black Friday, too.