Chinese officials on Saturday offered a lengthy rebuttal to accusations by the World Health Organization that they had been slow to share data about the possible origins of the coronavirus, blasting some in the organization as political "tools” whose remarks were "intolerable.”

Scientists from the Chinese Center for Disease Control and Prevention made the remarks at a news conference after weeks of mounting criticism from the WHO.

The WHO’s accusations referred specifically to the recent revelation that Chinese scientists had data on environmental and animal samples collected in Wuhan, the city in central China where the virus first emerged, that they had not shared earlier. On Thursday, a top WHO official said that China’s "lack of data disclosure is simply inexcusable.”