A Camarillo solar-panel company was among the targets of hacking by Chinese military officers, the U.S. Department of Justice announced on Monday.

Thousands of files were stolen from SolarWorld Industries America Inc. in Camarillo and a manufacturing facility in Oregon in 2012, according to a grand jury indictment returned in the U.S. District Court for the Western District of Pennsylvania.

The documents, alleged to have been taken by an officer named Wen Xinyu, related to cash flow, production-line information, and privileged attorney-client communications in trade litigation by SolarWorld against competing Chinese companies.

“Such information would have enabled a Chinese competitor to target SolarWorld’s business operations aggressively from a variety of angles,” the indictment read.

The widespread indictment – which also alleges Chinese officers hacked into nuclear and metal companies, and a steel workers' union – is the first criminal hacking charge brought by the government against specific foreign officials.

Wen and four other military officers face 31 counts, including economic espionage, trade secret theft, and conspiracy to commit computer fraud.

Cyber espionage has been an issue creating tension between the United States and China and is a top national security concern. The Chinese government reacted strongly to the indictment on Monday, denying the charges, demanding the U.S. retract the indictment and warning of repercussions if it wasn’t. Either way, there is virtually no chance that the officers, who reside in China, will ever see the inside of a U.S. courtroom.

SolarWorld has been in Camarillo since 2006 and manufactured solar panels there until a facility was opened in Oregon in 2009. It is owned by German company SolarWorld AG, which is phasing out administrative and research activity at the Camarillo plant, expected to close by the end of the year.

The company was aware of the alleged Chinese hacking in 2012 and tightened its security, spokeswoman Devon Cichoski told the Ventura County Star newspaper in a story posted on Monday.

The Star quoted Cichoski as saying SolarWorld was “deeply troubled by allegations that Chinese military officials illegally hacked into our computer systems,” and applauded the actions of the Justice Department.