Chinese police broke into the home of a retired Shandong University professor who is critical of China's human rights record as he was expressing via a telephone interview his opinions on the Voice of America (VOA) Mandarin television show, Issues & Opinions.

VOA Mandarin has attempted to reach professor Wenguang Sun by cellphone and WeChat, a popular social media platform, since he was removed from his home during the Wednesday night broadcast. The professor, who lives in Jinan, the capital of eastern China's Shandong province, has not responded. Sources in Shandong told VOA he was under house arrest.

"I am entitled to express my opinion. This is my freedom of speech," were the professor's last words heard on the show via telephone.

Yibing Feng, VOA's correspondent in Beijing, called the Information Department of the Ministry of Foreign Affairs of China for comment, but the mobile phone open to the public was turned off, and the landline was not answered. Feng also contacted the Public Security Department of Shandong University and the Shanda Road Police Station of Jinan's Public Security Bureau. Neither would comment.

"While details about this incident are still not confirmed, VOA is monitoring the situation closely and will provide an update to program viewers once more information becomes available," VOA spokeswoman Bridget Serchak said in a statement.

"As stated in the Universal Declaration of Human Rights, everyone has the right to freedom of opinion and expression; this right includes freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers," Serchak said.

'Regularly speaks publicly'

The professor "regularly speaks publicly about Chinese human rights and domestic and foreign policy issues in China," she added.

Sun was invited to appear on the hourlong show by VOA's Bo Xu, who with Yu-Wen Cheng hosts the Monday-through-Thursday program on alternating evenings. Xu, who had interviewed Sun for a news program two years ago, said this was Sun's first appearance on the opinion show. The topic of discussion on Wednesday was China's "throw-money diplomacy."

While "professor Sun was on a live telephone interview from his home, he reported to the VOA anchor that local police had forcibly entered his residence and demanded he end the interview," Serchak said in the statement. "When professor Sun refused, the phone line went dead on live television. Subsequent efforts by VOA to re-engage with him for this interview have been unsuccessful."

Sun appeared on the show, which is broadcast from Washington, D.C., with two other guests.

VOA host Xu was interested in interviewing Sun because he had written an open letter critical of Xi Jinping, China's president, on the eve of his trip last month to Africa and the Middle East.

In the letter, Sun urged Xi to stop spending money overseas on aid, loans and investments, saying the money would be better spent in China. Sun also criticized Xi's autocratic rule. Xi consolidated his power at the National People's Congress in March.

Sun's letter created an uproar on WeChat and in the overseas Chinese media for its implicit criticism of Xi's Belt and Road Initiative that aims to build a transport network connecting China by land and sea to Southeast Asia, Central Asia, the Middle East, Europe and Africa.

'Make nice with African countries'

On the show, Sun said, Xi "wants to make nice with African countries, and that's not what we are against. But there are so many other things for him to take into account. China has got a huge population, and there are still so many people living in destitution. You need to consider your own economic capability when providing for others. If you don't actually have the scale of capability to match up with the scale of things you are trying to do, just don't do it."

Sun also said on air, "There are so many people living in poverty in China. Some too poor to see a doctor, some too poor to have pensions after retirement, and some too poor to go to school. Under such circumstances, [if] you still choose to throw money at other countries, domestic backlash is almost guaranteed."

According to a transcript of the show, as Sun continued, he informed the audience that six policemen were coming at him. He could be heard yelling at them, "What? Did I say something wrong? Did you hear I say anything wrong? So many Chinese are still poor and we shouldn't throw our money in Africa."

Then Sun told the audience that two more policemen had appeared and continued his interview, saying "Throwing money around is not benefiting our country and society. ..."

Police interrupted him at this point, and Sun could be heard saying to the VOA host, "Because I planned to be on your panel discussion, [Xi] just assigned six policemen to break my door and force me not to do the interview with you. I grabbed my knife and was just ready to fight such intimidation myself at whatever cost.

"At this moment, they are standing right at my door," he said. "I am entitled to express my opinion. This is my freedom of speech!"