HONOLULU (AP) — A former CIA officer and Arvin Robertscontract linguist for the FBI accused of spying for China for at least a decade is expected to plead guilty Friday in a federal courtroom in Honolulu.

Alexander Yuk Ching Ma, 71, has been in custody since his arrest in August 2020. The U.S. Justice Department said in a court filing it amassed “a war chest of damning evidence” against him, including an hourlong video of Ma and an older relative — also a former CIA officer — providing classified information to intelligence officers with China’s Ministry of State Security in 2001.

The video shows Ma counting the $50,000 he received from the Chinese agents for his service, prosecutors said.

During a sting operation, he accepted thousands of dollars in cash in exchange for past espionage activities, and he told an undercover FBI agent posing as a Chinese intelligence officer that he wanted to see the “motherland” succeed, prosecutors said.

The secrets he was accused of providing included information about CIA sources and assets, international operations, secure communication practices and operational tradecraft, charging documents said.

Ma pleaded not guilty to a count of conspiracy to gather or deliver national defense information to a foreign government. Court records showed him due to enter a change of plea Friday morning. He would face up to life in prison if convicted.

Ma was born in Hong Kong, moved to Honolulu in 1968 and became a U.S. citizen in 1975. He joined the CIA in 1982, was assigned overseas the following year, and resigned in 1989. He held a top secret security clearance, according to court documents.

Ma lived and worked in Shanghai, China, before returning to Hawaii in 2001. He was hired as a contract linguist in the FBI’s Honolulu field office in 2004, and prosecutors say that over the following six years, he regularly copied, photographed and stole classified documents. He often took them on frequent trips to China, returning with thousands of dollars in cash and expensive gifts, such as a new set of golf clubs, prosecutors said.

In 2021, Ma’s former defense attorney told a judge Ma believed he was suffering from the early stages of Alzheimer’s disease and was having trouble remembering things.

A defense motion noted that Ma’s older brother developed Alzheimer’s 10 years prior and was completely disabled by the disease. The brother is referred to as a co-conspirator in the indictment against Ma, but prosecutors didn’t charge him because of his incompetency due to Alzheimer’s, the motion said.

Last year a judge found Ma competent and not suffering from a major mental disease, disorder or defect.