Amazon.com said on Thursday its Kindle Fire tablet computer is sold out, raising expectations that the Internet retailer will launch at least one new version of the device at an event next week.

Less than one year ago, Amazon introduced Kindle Fire. Kindle Fire quickly became the most successful product launch in the history of Amazon.com and is the #1 best-selling product across the millions of items available on Amazon since its introduction 48 weeks ago. Today, Amazon announced that Kindle Fire is sold out, and that in just nine months, Kindle Fire has captured 22% of tablet sales in the U.S.

Amazon Chief Executive Jeff Bezos said the 7-inch Kindle Fire has grabbed 22 percent of U.S. tablet sales since it hit stores in November at $199, well below the price of Apple's market-leading iPad.

Amazon is holding a media event on September 6 in Santa Monica, California, fueling speculation that it will launch new tablet devices.

A week after Amazon's event, Apple is planning a news conference where it is expected to unveil a new version of its iPhone. However, some analysts also expect Apple to launch a smaller tablet this year to compete with the cheaper Kindle Fire.