Industrialist Elon Musk has come under attack from the Joe Biden government for his comments on American infectious disease expert Anthony Fauci.
The White House called Elon Musk's comments on Fauci "incredibly dangerous", "disgusting", and "divorced from reality".
Earlier, Musk had sought action against Fauci, who led USA's response to the Covid-19 pandemic.
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Musk had tweeted an edited photograph showing Fauci telling Biden "just one more lockdown, my king". In another tweet, the owner of Twitter said that his "pronouns are Prosecute/Fauci".
"These personal attacks that we've been seeing are dangerous on Dr. Fauci and other public health professionals as well," said White House spokesperson Karine Jean-Pierre.
"Dr. Fauci has served under seven Republican and Democratic presidents. We cannot forget that.... His work on infectious disease from HIV Aids to Covid has saved countless lives," she said.
"We are fortunate, I should say, that he has devoted his career and his life and his exceptional talent to America's public health."
Fauci, 81, is due to step down this month from his roles in government as Biden's chief medical advisor, as well as director of the National Institute for Allergies and Infectious Diseases, which he has headed since 1984.
(With agency inputs)