A Chinese official has suggested without proof that the United States army may be responsible for bringing the coronavirus into China.

Zhao Lijian, a foreign ministry spokesman, posted the allegation on Twitter late Thursday, March 12.

He was echoing similar conspiracy theories disseminated via Chinese social media that blame the U.S. for the global pandemic.

Chinese officials and a prominent health expert have already claimed that the virus may have originated elsewhere.

Zhao posted a video in his tweet showing the head of the U.S. Centers for Disease Control and Prevention testifying before Congress that some Americans who were believed to have died from the flu were posthumously diagnosed with the COVID-19 illness.

Zhao tweeted: "CDC was caught on the spot. When did patient zero begin in US? How many people are infected? What are the names of the hospitals?"

"It might be US army who brought the epidemic to Wuhan. Be transparent! Make public your data! US owes us an explanation!"

1/2 CDC Director Robert Redfield admitted some Americans who seemingly died from influenza were tested positive for novel #coronavirus in the posthumous diagnosis, during the House Oversight Committee Wednesday. #COVID19 pic.twitter.com/vYNZRFPWo3

— Lijian Zhao 赵立坚 (@zlj517) March 12, 2020

2/2 CDC was caught on the spot. When did patient zero begin in US? How many people are infected? What are the names of the hospitals? It might be US army who brought the epidemic to Wuhan. Be transparent! Make public your data! US owe us an explanation! pic.twitter.com/vYNZRFPWo3

— Lijian Zhao 赵立坚 (@zlj517) March 12, 2020

What sparked accusation that U.S. brought virus to China?

This lashing out against the U.S. occurred as Beijing is angrily hitting back at U.S. officials for calling the disease the "Wuhan virus".

US officials have angered China by linking the virus with the country.

Secretary of State Mike Pompeo has been calling it the "Wuhan virus".

The Chinese foreign ministry has rejected the term as "despicable" and "disrespecting science".

Robert O'Brien, the US national security adviser, insisted on Wednesday that the birthplace of the virus was China.

"This virus did not originate in the United States, it originated in Wuhan," O'Brien said at the Heritage Foundation think tank.

"Unfortunately, rather than using best practices, this outbreak in Wuhan was covered up."

He also said China had "cost the world community two months to respond" to the epidemic.

Had China been more cooperative and allowed foreign experts on the ground earlier, he said, "we could have dramatically curtailed what happened both in China and what is now happening across the world".

Covid-19 has now killed nearly 5,000 people and infected more than 130,000 worldwide.

China denounces "Wuhan virus" label as "extremely immoral"

In response, Chinese foreign ministry spokesman Geng Shuang on Thursday called OBrien's remarks "extremely immoral and also irresponsible".

Geng said China's tough quarantine measures to contain the virus had won the world "hard-won precious time".

In China, the head of China's Center for Disease Control and Prevention has said that the source of the virus was wild animals sold at a market in the central city of Wuhan.

Top photo via Getty