A customer chooses Apple products at a gadget shop in Zhongguancun on Sunday. Beijing's quality watchdog said they will prohibit unauthorized retailers from using the Apple logo or using any brand name associated with Apple.

Unauthorized sellers of Apple products in Zhongguancun have been told to cover up the Apple logo as the city's quality watchdog attempts to tighten control over the nation's top center for the distribution of electronic products.

An official at Beijing's quality and technical supervision bureau has confirmed that the city will prohibit unauthorized retailers from using the Apple logo or using any brand name associated with Apple, such as "Apple authorized reseller" or "Apple direct retailer".

"We have received frequent inspections from the city's industry and commerce bureau in recent days," said the manager of a store surnamed Qiao. His store mainly features Apple products in Zhongguancun.

As of Sunday, the response to the ban from unauthorized Apple sellers had been sluggish, with some owners merely covering their Apple logos with blank sheets of paper, or just covering part of the Apple logo, and employees at unauthorized retailers could still be seen dressed in T-shirts bearing the Apple logo.

"If you come back a few days later, everything will be back as it was," said Qiao.

The response to the ban also varies depending on the mall, with more sellers from malls such as Hailong and Top Electronics City responding than those from Zhongguancun E-plaza and Como Electronics City.

Qiao estimated there are more than 50 vendors selling Apple products in Top Electronics City alone, all of them unauthorized, and there are 11 electronics malls in Zhongguancun, China's so-called Silicon Valley.

"Apple products are much more popular than other brands, so all vendors are eager to get into the business," said an Apple product dealer at Top Electronics City who refused to be named.

The campaign, which will reportedly last a month, comes after the discovery of fake Apple stores in Kunming, capital of Yunnan province, and Southwest China's Chongqing, which attracted worldwide media attention.

Most the stores exposed by media remain in business, as Apple China has so far not responded to the issue of possible copyright infringements.

Officials say the large number of unauthorized Apple resellers affects the business of authorized ones, of which there are five in Zhongguancun.

According to Gao Zhu at Hoosing - an authorized reseller - the unauthorized resellers are in better position as they also offer smuggled and fake Apple products.

"It takes some expertise to tell the difference between the three kinds, or you risk being conned," he said.

"The logo we use is a relatively small Apple logo, unlike theirs (unauthorized stores)," he added.

Numerous cases of cheating at the electronics malls in Zhongguancun have been reported in the past few years, severely tainting the reputation of the whole area.

Meanwhile, the prevalence of hard-selling in these malls is often intimidating, with some unauthorized vendors behaving even more aggressively. The self-introduction of being a reporter could work dramatically to shift their attitude from hospitality to hostility in an instant.

One worker responded to the question about when the Apple logo was covered nonchalantly, "four months ago."

"It can take a long time to establish a good reputation, but damaging it is much easier," Gao said.

There are more than 50,000 people employed at the 11 electronics malls in Zhongguancun.