Beijing has expressed deep concern about the latest economic espionage allegations targeting Chinese nationals in the United States, a case that observers say highlights growing economic friction between the two countries.

China is seeking further details and will work to safeguard the rights and interests of its nationals, Foreign Ministry spokesman Hong Lei said on Wednesday.

Hong's remarks followed the announcement that the US has charged six Chinese nationals with stealing mobile phone technology from two US chipmakers where some of them worked. A 32-count criminal indictment says the six were acting on behalf of universities and companies controlled by the Chinese government.

One of the suspects, Zhang Hao, 36, was visiting the US for a conference when he was arrested on Saturday in Los Angeles after arriving on a flight from China, the US Justice Department said on Tuesday. The other five are believed to be in China.

US prosecutors say Zhang, a former employee of Massachusetts-based Skyworks Solutions and now a Tianjin University professor, and the others established a company, ROFS Microsystems, in Tianjin with secrets stolen from Skyworks and another US firm, Avago Technologies. Zhang graduated from USC with a doctorate in electrical engineering.

Two other suspects, Pang Wei and Chen Jingpin, deny stealing technology, according to the indictment. Pang, 35, is a former employee of California-based Avago. He also is a professor at Tianjin University, and also graduated from USC with a doctorate in electrical engineering.

A publicity department official at the university, surnamed Song, said further details are being sought and a public response will be issued.

This is the 11th case of alleged economic espionage brought in the US under a 1996 law, and the six suspects could face lengthy prison sentences if convicted.

Teng Jianqun, an expert on US studies at the China Institute of International Studies, said the US is overly suspicious about the protection of intellectual property rights.

Li Haidong, a professor of US studies at China Foreign Affairs University, said the two countries have seen growing friction in the economic sector, but these problems, along with others, have to be properly addressed to avoid disrupting the development of high-level ties.

On Wednesday, when asked whether the Obama administration feels that the trajectory of the US relationship with China is heading in the wrong direction with the indictment at a time that Chinese President Xi Jinping will visit the US this fall, White House Principal Deputy Press Secretary Eric Shultz said he would not going comment on the decisions by prosecutors.

"Generally speaking, as you point out, we are looking forward to that visit later this year. And we have a complicated but good relationship with China. We continue to work closely with them on a number of issues and we look forward to robust discussions on that visit later this year," he told reporters.

Last year, the US indicted five Chinese military officers for allegedly hacking information from US nuclear, metal and solar companies. The Defense Ministry in Beijing issued a denial and summoned the US military attache.

Over the years, some US espionage charges against Chinese and Chinese Americans have been either dismissed or reduced. In March this year, US prosecutors dismissed eight-count charges against Xiafen "Sherry" Chen, an employee of the US National Weather Service of illegally accessing restricted federal computer database that contains information about the nation's dams, stealing information and lying to federal investigators. Prosecutors had earlier said Chen illegally accessed the restricted information after meeting with former Chinese colleague on a visit to family in China in 2012.

On Thursday afternoon, leaders of the Asian Pacific American community will join several members of the US Congress, including Ted Lieu, Judy Chu, Mike Honda and Grace Meng, to call for Attorney General Loretta Lynch to investigate and determine whether race and national origin were factors in the case of Sherry Chen.

They will seek to understand whether there is any written or unwritten policy, program, pattern or practice of additional civil rights classifications such as religion and gender being used by Federal agencies in targeting Federal employees and contractors, or any American, for surveillance, arrest, security clearance denials or other adverse actions in the implementation of national security policies, according to the organizer of the event.

In 1999, Chinese American scientist Wen Ho Lee, who was born in Taiwan, was charged by a federal grand jury with stealing secrets about the US nuclear arsenal for China. Lee was charged on 59 counts, but the US government, after conducting a separate investigation, was ultimately only charged him with improper handling of restricted data.

In 2000, President Bill Clinton issued a public apology for Lee's treatment during the investigation, and Lee was also compensated for improper conduct by government departments and news media.

Contact the writers at zhaoyinan@chinadaily.com.cn and chenweihua@chinadailyusa.com

Li Xiang in Tianjin contributed to this story.