Washington (AFP) - US Attorney General Jeff Sessions announced charges Thursday against Chinese and Taiwan companies for theft of an estimate $8.75 billion worth of trade secrets from US semiconductor giant Micron.

Sessions said the case was the latest in a series that are part of a state-backed program by Beijing to steal US industrial and commercial secrets.

"Taken together, these cases and many others like them paint a grim picture of a country bent on stealing its way up the ladder of economic development and doing so at American expense," Session said.

"This behavior is illegal. It is wrong. It is a threat to our national security. And it must stop."

The indictment released in the US district court in San Jose, California alleges that Chinese state-owned Fujian Jinhua Integrated Circuit Co. and privately owned United Microelectronics Corporation of Taiwan, along with three UMC executives, conspired to steal Micron trade secrets to help UMC and Fujian Jinhua develop DRAM chips used in many computer processors.

It said the three Taiwanese men -- Stephen Chen Zhengkun, He Jianting and Kenny Wang Yungming -- all previously worked at Micron and stole its technology when they joined UMC with the express purpose of transferring it to Fujian Jinhua, a two-year-old firm.

Chen was originally a top executive at Micron, then moved to lead UMC, and subsequently became president of Fujian Jinhua.

The move posed a major threat to Micron, a company valued at around $100 billion and which controls 20-25 percent of the global market for DRAM, or dynamic random-access memory, chips.

The indictment came four months after Fujian Jinhua won a patent dispute with Micron in a Chinese court, gaining an order for the US company to stop sales in China of more than a dozen solid-state drives, memory sticks and chips.

In retaliation, the US Commerce Department on Monday placed heavy restrictions on Fujian Jinhua's ability to buy US machinery and materials for its factories that would boost its DRAM production capabilities.

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The new restrictions mean US firms will need special approval to export products intended for use by state-owned Fujian Jinhua Integrated Circuit Company, Ltd., according to a statement.

In addition to the criminal charges announced Thursday, the Justice Department filed a civil lawsuit to block imports of any UMC and Fujian Jinhua products using stolen Micron technology.

In the past two months the Justice Department has also indicted 12 Chinese, including three intelligence officials, in an alleged five-year plot to steal jet engine technology from major US and French companies who supply the world's airlines.