In a hearing before the Senate homeland security and governmental affairs committee, Wray described China as the "greatest counterintelligence threat" to the United States, describing "aggressive activity" to target research on vaccines, treatments, testing technology and other coronavirus matters.
Wray said in his opening statement that the FBI has opened a new China-related counterintelligence case "approximately every 10 hours" and that nearly half of the 5,000 active counterintelligence cases underway are related to China.
"Sometimes, without being too descriptive in an open setting, we can almost track a news report form some company or research institution that is announcing or revealing some progress ... and then almost within days we will see cyber targeting that ties back to Chinese actors focusing on those institutions," Wray said.
The FBI and the Cybersecurity and Infrastructure Security Agency previously warned in May that China and its affiliates had been observed "attempting to identify and illicitly obtain valuable intellectual property and public health data related" to the pandemic.
In July, the United States charged two Chinese nationals with hacking pharmaceutical companies that are developing coronavirus vaccines.
Wray testified Thursday that China's efforts seek to essentially allow the country to "jump to the front of the line" in regards to research and drug development by stealing information from other nations.
He added that Russia and Iran have also been observed targeting companies conducting COVID-19 research and that the scope of China's actions extends beyond the United States.
"They are targeting not just American companies, American research institutions, but also similar institutions among some of our closest allies and targeting PII, personally identifiable information, of Americans," he said. "Chinese hackers have essentially stolen the PII of about half the adult population of the United States."