A customer (R) checks an iPad at the Apple store in Shanghai. Protective cases for the second generation iPad are being sold on Chinese e-commerce website Alibaba -- even before Apple has launched the new device -- and suggest the next model will have a camera.

Protective cases for the second generation iPad are being sold on Chinese e-commerce website Alibaba -- even before Apple has launched the new device -- and suggest the next model will have a camera.

Alibaba spokesman John Spelich told AFP on Tuesday the company had been asked to remove the listings, which showed brightly coloured silicon cases with a small hole in the back on sale for less than three dollars each.

"Shortly after we were made aware, through blog reports, of the presence of these listings, we received a legitimate take down request and we have been doing so since last week," Spelich said, without naming the complainant.

An AFP search for iPad2 cases found seven listings on Alibaba -- a trading platform for small businesses -- mostly from suppliers based in southern China who were accepting orders for a minimum 200-500 units.

Apple's touchscreen allows users to watch video, listen to music, play games, surf the Web and read electronic books, but the next model is also expected to feature a camera and USB port.

The company is predicted to launch iPad2 this year after selling more than eight million of the original devices between April, when it went on sale in the United States, and the end of September, Apple's last reporting period.

In China -- the world's biggest Internet market with 450 million users, according to the last official count, and the major producer of Apple products -- hundreds queued for the first official iPads when they were launched in the country in September.

Goldman Sachs predicts iPad sales could top 37.2 million units in 2011 and technology research firm Gartner forecasts total tablet computer sales of 55 million units this year.

Some observers had expected Apple to unveil iPad2 at the US International , which starts Thursday.

But the California-based company is shunning the massive electronics trade show, which attracts tens of thousands of buyers and sellers from around the world to Las Vegas.

Apple is notoriously secretive about new products but it's security system has been breached in the past.

A prototype of Apple's 4th generation iPhone turned up in Vietnam in May, a month before the gadget's global launch.