The US Justice Department has announced a series of criminal cases tracing the illegal flow of sensitive technology, including Apple’s software code for self-driving cars and materials used for missiles, to foreign adversaries like Russia, China and Iran.

Some of the alleged theft dates back several years but officials are drawing attention to the cases now to highlight the work of a taskforce created this year to disrupt the transfer of goods to foreign countries.

“We are committed to doing all we can to prevent these advanced tools from falling into the hands of adversaries who wield them in a way that threatens not only our national security but democratic values everywhere,” said assistant attorney general Matthew Olsen, who heads the Justice Department’s national security division.

One of the cases, unsealed on Tuesday in federal court in Los Angeles, accuses a former software engineer from Apple of taking proprietary data related to self-driving cars before his last day at the company in 2018 and then boarding a flight from San Francisco to China on the night FBI agents were searching his house.

Other cases disclosed on Tuesday have resulted in arrests. One defendant, Liming Li, 64, was arrested earlier this month on charges that he stole thousands of sensitive files from his California employer, including technology that can be used in the development of nuclear submarines and military aircraft, and used them to help competing Chinese businesses.

He has been in custody since his arrest.

Two Russian nationals, Oleg Sergeyevich Patsulya and Vasilii Sergeyevich Besedin, were arrested in Arizona this month on charges of conspiring to send aircraft parts to Russian airline companies.

The Justice Department also unsealed a separate criminal case accusing a Chinese national of conspiring to transmit isostatic graphite, a material that can be used in the nose of intercontinental ballistics, to Iran in violation of US sanctions.

The departments of Justice and Commerce earlier this year launched the Disruptive Technology Strike Force as a way to prevent US adversaries from acquiring sensitive technology.