Foster worked as a sociology professor at Guangdong University of Foreign Studies in southern China for a total of five years before he was charged with theft and sent to jail. Courtesy of Stuart Foster hide caption

itoggle caption Courtesy of Stuart Foster

Chinese mourners placed flowers and lit candles at the scene of an attack last week that killed 39 people in the northwestern Chinese city of Urumqi. When people used social media to call for a protest, authorities tried to break up the gathering. Frank Langfitt/NPR hide caption

itoggle caption Frank Langfitt/NPR

A photo released by China's Xinhua News Agency shows police standing guard near a blast site in downtown Urumqi. Officials say 31 people died in the attack. Cao Zhiheng/AP hide caption

itoggle caption Cao Zhiheng/AP

A worker turns a valve at an underground gas storage facility near Striy on Wednesday. Russia has said state-controlled exporter Gazprom will supply China with natural gas via a Siberian pipeline beginning in 2018. Gleb Garanich/Reuters/Landov hide caption

itoggle caption Gleb Garanich/Reuters/Landov

The building housing China's Unit 61398, a division of the army linked to hacking operations, is seen in Shanghai last year. The U.S. says the group worked to steal trade secrets from American companies. AP hide caption

itoggle caption AP

Press materials are displayed on a table at the Justice Department in Washington on Monday before Attorney General Eric Holder was to speak at a news conference. Charles Dharapak/AP hide caption

itoggle caption Charles Dharapak/AP

Policemen ask people to leave a street near to the Chinese embassy in Hanoi on Sunday. A call for further anti-China protests appeared to have fizzled in the capital, with authorities deploying heavy security around the Chinese embassy and other suspected protest sites. Hoang Dinh Nam /AFP/Getty Images hide caption

itoggle caption Hoang Dinh Nam /AFP/Getty Images

A Taiwanese bicycle factory in Ho Chi Minh City burns after mobs angered over Chinese moves in the South China Sea mistakenly targeted the facility, thinking it was Chinese owned. Jeff Nesmith/AP hide caption

itoggle caption Jeff Nesmith/AP

Among other courses, the China Executive Leadership Academy in Shanghai teaches public relations to government officials, including mock TV shows and mock press conferences. NPR's Frank Langfitt took this photo from a control room, because the presence of a foreign reporter in class rattled some of the participants. Frank Langfitt/NPR hide caption

itoggle caption Frank Langfitt/NPR