BEIJING, March 12 (Reuters) - A spokesman for China’s Foreign Ministry suggested on Thursday the U.S. military might have brought the coronavirus to the Chinese city of Wuhan, which has been hardest hit by the outbreak, doubling down on a war of words with Washington.

China has taken great offence at comments by U.S. officials accusing it of being slow to react to the virus, first detected in Wuhan late last year, and of not being transparent enough.

On Wednesday, U.S. National Security Adviser Robert O’Brien said the speed of China’s reaction to the emergence of the coronavirus had probably cost the world two months when it could have been preparing for the outbreak.

In a strongly worded tweet, written in English on his verified Twitter account, Chinese Foreign Ministry spokesman Zhao Lijian said it was the United States that lacked transparency.

“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!” Zhao wrote.

Zhao, an avid and often combative Twitter user, did not offer any evidence for his suggestion that the U.S. military might be to blame for the outbreak in China.

Earlier on Thursday, Zhao’s fellow Foreign Ministry spokesman Geng Shuang criticized U.S. officials for “immoral and irresponsible” comments that blamed Beijing’s response to the coronavirus for worsening the global impact of the pandemic.

Asked about O’Brien’s comments, Geng told a daily news briefing in Beijing on that such remarks by U.S. officials would not help U.S. epidemic efforts.

China’s efforts to slow the spread had bought the world time to prepare against the epidemic, he added.

“We wish that a few officials in the U.S. would at this time concentrate their energy on responding to the virus and promoting cooperation, and not on shifting the blame to China.”