A former Apple employee allegedly stole trade secrets from the company with the intent to bring them to a new employer, The Mercury News reports today. The materials notably involved autonomous vehicle technology — a business that Apple has reportedly been working on for years under a shroud of secrecy.

Xiaolang Zhang was stopped by federal agents at San Jose International Airport after purchasing a “last-second” ticket to China aboard Hainan Airlines. According to a tweet from Oakland-based crime reporter Henry K. Lee, Zhang took secret documents from Apple while on paternity leave, telling authorities that he had placed the data on his wife’s laptop. He was charged today with theft of trade secrets in the U.S. District Court for Northern California.

Both sources claim that Zhang was going to work for XMotors, a company that says it’s building “intelligently connected and all-electric cars for the young generation.” Also known as Xiaopeng Motors, XMotors is listed as having offices in Beijing and Guangzhou, China, as well as Mountain View, California, but has a relatively spartan website. Its Twitter account says that it counts Alibaba, Foxconn, and IDG Capital as investors, and has developed an electric car called the XPeng G3.

According to the Mercury News, Zhang was given “broad access to confidential internal databases” as part of his work on a team developing autonomous cars. After he informed Apple that he would be leaving the company and going to work for XMotors, Apple investigators searched his two company-issued phones and laptop. They discovered that he had been aggressively downloading confidential files, as well as visiting Apple’s labs and removing items during the paternity leave. Zheng reportedly admitted to taking the items and secret documents, and was trying to leave the country when he was stopped by the FBI.

A LinkedIn profile apparently belonging to Zhang suggests that he had worked with Apple since December 2015, and previously spent over four years at Marvell Semiconductor. His specialties included architecting chips and system solutions, including high-speed interfaces and board designs. The specific documents and items he took from Apple are unknown, and are likely to remain under seal during the criminal proceedings.

Updated on July 11 at 6:59 a.m.: In a statement, XMotors is distancing itself from Zhang, stating that he joined the company in May and was terminated after the company learned that U.S. authorities were investigating him. The company claims that “[t]here is no indication that he has ever communicated any sensitive information from Apple to XMotors,” and says that it strictly abides by U.S. and Chinese laws.