President Donald Trump has threatened to punish China further after an indictment against one of its spies was unsealed Wednesday by the Justice Department.

The president has been railing against Beijing’s intellectual property theft and unfair trade practices for years, hammering the issue since his 2016 presidential campaign. He is reportedly furious over this latest development and warned there is “a lot more to do” to retaliate against China, adding:

“The Chinese people have lived too well for too long.”

The Chinese Foreign Ministry has finally responded to the indictment of Xu Yanjun on charges of economic espionage against GE Aviation in Dayton, Ohio. The principal spokesman for the ministry, Lu Kang, told reporters the charges were “pure fabrication,” adding:

“We hope the American side can justly, and in accordance with the law, safeguard the legal rights of the Chinese national.”

The indictment released by the Justice Department earlier this week provides a detailed case against Xu, who was reportedly engaged in his activities for nearly four years before his arrest in Belgium in April. He faces up to 50 years in prison on those charges.