(Bloomberg) -- Australian journalist Cheng Lei said China jailed her for sharing an official briefing document just before the government released it, an act that led to some three years of detention.

In an interview with Sky News on Tuesday, Cheng said she gave the information to others before she went on air for a show she was hosting.

“Essentially you broke an embargo?” Sky News journalist Annelise Nielsen. “By a few minutes?”

“Yes,” the Australian replied. Cheng didn’t say what type of document she shared or with whom. 

See: China Frees Detained Australian in Sign of Improving Ties

The interview was the first given by Cheng since she was released last week, a development that signaled improving ties between Canberra and Beijing. China’s spy agency said Cheng pleaded guilty to passing national secrets to an overseas institution and that she was sentenced to two years and 11 months in prison. That was the first time Beijing provided details on a verdict or sentencing in Cheng’s case, which involved a closed-door trial a year and a half ago.

Cheng’s detention in 2020 happened at a time of worsening ties between the nations and came months after the government of then-Prime Minister Scott Morrison called for an independent probe into the origins of the coronavirus. Her arrest sparked fears that Beijing targeted the mother of two to exert pressure on Canberra.

Relations between the countries have improved since the election of Prime Minister Anthony Albanese’s center-left Labor government in 2022, including the restarting of high-level ministerial meetings and the ending of several export restrictions by Beijing. 

Albanese plans to visit Beijing this year, Australian companies are once again shipping coal to China and the two countries announced a deal aimed at eliminating China’s tariffs on barley. 

Cheng hosted business shows on Chinese state media from 2012 and was well known among Beijing’s circle of diplomats and journalists. She said in the Sky News interview that the police who came to get her from her apartment warned her she would not be returning for some time.

“As we were leaving they said, ‘Turn off the power and water, take some clothes, take some toiletries,’” she said.

Cheng said she had recurring nightmares while in prison and felt like she was “buried alive.” She said she would imagine conversations with her loved ones or listen to fake radio stations in her head.

While the Chinese authorities said she was given access to fresh air for 15 minutes a day, Cheng said that meant a window at the top of a room would be opened “but the curtains are still drawn.”

“I certainly didn’t feel there was fresh air,” she said. “You never saw anything except the blue curtains, the mottled carpet and the beige padded walls.”

More: Australian Detained in China Misses Her Children, Sunshine

Cheng said she had felt that Australia showed a “noticeable increase in energy” for consular visits since the change of government. The Australian journalist said Foreign Minister Penny Wong sent her a personal note at one point that made her feel “that she was a friend who was trying to help me.”

(Updates with more comments from Cheng Lei and with more context.)

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