After a mass murder at a marijuana farm, a Chinese diplomat visited an organization that has been the subject of investigations. The meetings reflect an international pattern of contacts between Chinese officials and suspected criminal networks.

The photos look like a routine encounter between a senior Chinese diplomat and immigrants in the American heartland: dutiful smiles, casual clothes, a teapot on a table, Chinese and U.S. flags on the wall.

But behind the images, there is a potentially concerning story. During two trips to Oklahoma, Consul General Zhu Di of the Chinese embassy visited a cultural association that has been a target of investigations into Chinese mafias that dominate the state’s billion-dollar marijuana industry. And the community leaders posing with him in the photos? A number of them have pleaded guilty or been prosecuted or investigated for drug-related crimes, according to court documents, public records, photos and social media posts.

“He’s meeting with known criminals,” said Donnie Anderson, the director of the Oklahoma Bureau of Narcotics and Dangerous Drugs Control, in an interview.

There is no indication of wrongdoing by the consul general, who is one of China’s top diplomats in the United States. Still, the encounters in Oklahoma reflect a pattern of contacts around the world between China’s authoritarian government and diaspora leaders linked to criminal activity — a subject of increasing concern among Western national security officials, human rights groups and Chinese dissidents.

U.S. and foreign national security officials have alleged that the Chinese state maintains a tacit alliance with Chinese organized crime in the U.S. and across the world. Mobsters overtly support pro-Beijing causes and covertly provide services overseas: engaging in political influence work, moving illicit funds offshore for the Chinese elite and helping persecute dissidents, according to Western officials, court cases and human rights groups. Chinese officials reciprocate by tolerating and sometimes supporting their illicit activities, according to those sources.