Buoyed by robust economic indicators, holiday shoppers smashed all-time online sales records on Thanksgiving and Black Friday by more than $1 billion, reports said.

Deal-hungry customers spent as much as $1 million per minute on the Internet at the height of Black Friday, e-commerce platform Shopify said.

The news came just weeks after the Conference Board found that consumer confidence was at its highest point in almost 17 years.

Online sales at the 100 largest U.S. Web retailers totaled approximately $7.9 billion on Black Friday and Thanksgiving, marking a nearly 18 percent increase from 2016, according to Adobe Analytics, the research arm of software company Adobe.

Customers spent a record-high $5 billion on Black Friday alone, compared to $3.34 billion last year, Adobe Analytics said.

Customers spent a record-high $5 billion on Black Friday alone, compared to $3.34 billion last year.

The $2.87 billion that Adobe found consumers spent online on Thanksgiving set another record, marking a sizable increase from the $1.93 billion in online Thanksgiving sales last year.

Roughly 40 percent of Black Friday online sales were made on mobile devices, marketing firm Criteo reported.

Shoppers are expected to set more records on Cyber Monday. Adobe Analytics forecasted $6.6 billion in online sales on Monday, which would be a 16.5 percent increase from last year’s figure.

Brick-and-mortar retail sales data were not immediately available, but industry analysts noted signs of a decline in physical store sales this year, Reuters reported.

Retail analytic firm ShopperTrak said that preliminary data indicate a 1.6 percent decline in foot traffic to retail stores on Thanksgiving Day and Black Friday, although the decline on Black Friday was less than 1 percent.

"There has been a significant amount of debate surrounding the shifting importance of brick-and-mortar retail, and the fact that shopper visits remained intact on Black Friday illustrates that physical retail is still highly relevant and, when done right, profitable," Brian Field, a senior executive at ShopperTrak, said in a statement.

The Mall of America in Minnesota says that 2,500 people were in line at the 5 a.m. opening Friday, in line with a year ago. Shoppers started queuing up as early as 5:45 p.m. on Thanksgiving.

Jill Renslow, Mall of America's executive vice president of business development, said stores like Nordstrom, Macy's and Best Buy were crowded. She said the items that caught shoppers' attention included were voice-activated devices like Amazon Echo, nostalgic toys, clothing and shoes.

With the jobless rate at a 17-year-low of 4.1 percent and consumer confidence stronger than a year ago, analysts project healthy sales increases for November and December.

The National Retail Federation trade group expects sales for that period to at least match last year's rise of 3.6 percent and estimates online spending and other non-store sales will rise 11 to 15 percent.

The Associated Press contributed to this report.