US President Donald Trump's rally and other events in Tulsa have "likely" contributed to the spike in the county's caseload, a local public health official told reporters on Wednesday. 

"In the past few days we've had almost 500 cases and we knew we had several large events a little over two weeks ago," Bruce Dart, director of the Tulsa City-County Health Department, said on being asked about Trump's campaign and the protests over racial injustice. 

"So I guess we just connect the dots."

Trump held his first campaign rally in Tulsa last month amid a surge in coronavirus infections in the nation. 

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The event which attracted thousands of supporters, who were not required to wear a mask, came under criticism from public health experts.

Tulsa has reported over 4,500 confirmed COVID-19 cases and 72 deaths.

Record increase

The US recorded more than 59,000 new COVID-19 cases on Wednesday, making it the biggest increase ever reported by a country in a single day, according to a Reuters tally.

There were nearly 10,000 new cases in Florida, nearly 9,000 in Texas and 7,800 in California.

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Deaths per day in the US also rose to the highest levels since early June, to more than 900.

Late on Wednesday, the total number of cases in the US crossed the grim milestone of 3 million cases.

Despite the rise in infections and deaths, Trump on Wednesday threatened to withhold federal funding if school districts did not bring their students back into the classroom in the fall.

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