Here is more from the Washington Post:
Alarms over the souring relationship went off in Beijing this year when
Department of Homeland Security agents at the San Francisco airport
stopped a half-dozen senior Chinese researchers, including some employed
by the China Institutes of Contemporary International Relations — an
influential think tank that answers to China’s intelligence agency. The
agents confiscated the researchers’ laptops and phones and demanded
their passwords, according to two people familiar with the incident, who
spoke on the condition of anonymity to discuss a sensitive issue.
Outraged Chinese scholars suspected the searches were politically
motivated and wrote to the State Department saying they would cancel
future trips to the United States, according to a copy of an email from
the think tank seen by The Washington Post. (The institute later resumed
travel to the United States after receiving State Department
assurances.)
The article notes that the Chinese have reached out to long-standing contacts at US think tanks in order to better understand the Trump Administration. China has even dispatched a number of former government officials for "Track 2" meetings with US think tankers, but those meetings have not been very useful because "Washington's most prominent think tanks are populated by establishment figures who lack close ties to [President] Trump."
Hudson Institute China scholar Jonas Parello-Plesner
recently said that CICIR is "an acknowledged part of the
Chinese Ministry of State Security: the equivalent of the
CIA running a front-end think tank."