Amazon.com Inc said on Tuesday its Prime Day sale was on track to be the biggest shopping event in its history by sales.
The world's largest online retailer said customers ordered more than three times as many Echo-family speakers than during Prime Day 2016, which at the time broke records for Amazon devices.
Third-party sellers sold over 50 percent more items on the site by noon local time (1900 GMT) than in the same time frame last year, Amazon said in a statement.
The company has not disclosed sales figures, overall or for the Echo. Analysts estimated last year's event brought in well over $500 million.
The news underscores Amazon's break-neck pace of growth as more shoppers order online instead of going to brick-and-mortar stores. It also highlights the winning formula of Amazon's shopping club Prime, the cornerstone of its business.