(CNN) -- In his first in-depth TV interview since his dramatic escape from house arrest, Chinese human rights activist Chen Guangcheng told CNN about his departure from China and his continuing concern for family and friends he left behind.
He also spoke about tasting freedom recently.
"I haven't been able to feel (nature) for a long time," said Chen, who is blind. "I had some time to soak in the sun and feel the breeze. I just felt I hadn't been able to do that in so long. I have missed out for too long. "
Asked about speaking out against China, he said, "It was natural for me, it was very natural for me. I feel it's in people's nature to want to stop evil and embrace the good."
His experience being under house arrest in China, he said, brought much suffering.
"I want to correct one thing here," Chen said. In the future, he continued, "let's not use the word 'house arrest,' but instead let's use the term 'illegal detention.' It's hard for me to describe what it was like during that time. But let's just say that my suffering was beyond imagination."
He made his comments Thursday morning in an exclusive with CNN's Anderson Cooper.
Chen's arrival in the United States on Saturday brought an end to a diplomatic firestorm between Beijing and Washington that erupted after he escaped from house arrest in the Shandong province.
Chen, 40, and his wife and children are in the United States for Chen to study at New York University under a fellowship.
Chen told CNN that he and his wife were beaten periodically in China.
"Yes, it was beyond everybody's imagination," Chen said. "But I don't want to talk about it right now."
Five days after arriving in the United States, Chen said he was still gathering his thoughts about his escape.
"After evading danger and the obstacles, I was able to get out of Dongshigu village (his home town) and then I called my good friend Guo Yushan in Beijing.
"He quickly led a team to find me and drove me to Beijing. I was able to talk extensively with him during the journey and found out what had been going on in the outside world. So Mr. Guo played a very important role in this process," Chen said.
Though staying in a safe place in Beijing, he began to worry about his safety, he said. He was also getting treatment for a foot injury, he said. He came up with a safer place to stay, he said.
He noted how acquaintances in China helped him.
"There's one thing I want to mention that may be a surprise to many people," Chen said. "When a group of people come together and accomplish something, they often fight for credit. In my case, all those people who went to Shandong to pick me up, when the news broke, they were fighting for risk instead of credit. They were all trying to claim responsibility to make others safer."
Chen, who's blind, fears the Chinese government may retaliate against acquaintances who helped him, he said.
"Of course, I'm very worried. We can see their retribution against my family since my escape has continued and been intensified," Chen said.
Shortly after Chen escaped from his village, his nephew, Chen Kegui, was arrested and accused of murder. Chen Kegui's father, who's Chen Guangcheng's brother, has fled his village in eastern China to Beijing to seek legal advice, his lawyer said Thursday.
"When dozens of men break into someone's house with weapons in the middle of the night, taking away your parent with a hood over his head and detain him without any legal basis and then go back to assault my nephew, he only reacted when he could no longer bear the beatings, and his actions would be self defense according to any Chinese law," Chen told CNN.
"They injured his head, and made him bleed for three hours, and his clothes were shattered and the sticks they used to beat him were bent, and if actions under such circumstances (were) not called self-defense, would there be any meaning left in having the term self-defense in Chinese law?" Chen added.
Chen asserted that the Chinese government seeks to convict his nephew under an unfair legal process.
"What they're doing now is not very different than what they did to me in 2006," Chen said. "They told my nephew no lawyers are willing to defend you. Then they tell lawyers outside (that) Chen Kegui has already hired lawyers. I experienced the same thing in 2006. Back then I told them clearly I have my own lawyers. I don't need you to appoint lawyers for me. But they forced ... a government-appointed lawyer onto me despite my protest."
In 2006, Chen was sentenced by a local Chinese court to four years and three months in prison on charges of damaging property and "organizing a mob to disturb traffic" in a protest, charges that his supporters called preposterous.
Chen rose to fame in the late 1990s because of his legal advocacy for what he called victims of abusive practices, such as alleged forced abortions, by China's family planning officials.
After he was released from prison in September 2010, he had been confined to his home along with his wife, mother and daughter.
Regarding his 2006 trial, Chen told CNN: "That whole process was just a farce of them investigating, prosecuting, trying and convicting all by themselves."
To ensure his nephew receives a fair trial, his case should be assigned to a court outside of Shandong, Chen said.
"Chen Kegui's case should be moved elsewhere, so he can have a fair trial and have his innocence and freedom back," Chen said. "China's own criminal procedure law means Shengdong authorities cannot be involved in Chen Kegui's case."
The case "is going to be a benchmark in testing China's rule of law. It's going to be a litmus test," Chen continued, "because in his case, what happened was not difficult to verify. The facts are clear. The key is whether or not they want to act based on facts and accordance with law."
On Saturday, the activist indicated through a translator that the U.S. government granted him partial citizenship rights. He asked people to work with him to "promote justice and fairness in China." And Chen said he was looking forward to recuperating in "body and spirit."
CNN's Roger Clark, Charlie Moore and Susan Chun contributed to this report.
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