Joe Biden and Bernie Sanders have hit out at Donald Trump’s handling of the coronavirus outbreak during the latest Democratic debate.
The pair faced off in a Washington TV studio with no audience in a move made to limit possible exposure to the virus.
With limited testing available, US officials have recorded nearly 3,000 cases and 65 deaths in the outbreak, up from 58 on Saturday.
In their first one-on-one debate, the two Democratic contenders to face Mr Trump in the November election clashed on the proper response to the coronavirus pandemic and other issues.
Both candidates accused the president of contributing to growing worries by spending weeks minimising the threat before declaring a national emergency on Friday.
“The first thing we have to do, whether or not I am president, is to shut this president up right now,” Mr Sanders said.
“He is undermining the doctors and scientists who are trying to help the American people.”
But the two disagreed sharply over how they would handle the crisis as president, and bickered repeatedly over their records on a range of issues from climate change to healthcare.
“People are looking for results, not a revolution,” Mr Biden said, taking a shot at his opponent’s promises to lead a political revolution to sweep in his anti-corporate economic agenda.
“We have problems we have to solve now. What’s a revolution going to do, disrupt everything in the meantime?”
Frontrunner Mr Biden also pledged to choose a woman as his running mate if he is the Democratic nominee.
“If I’m elected president, my cabinet, my administration, will look like the country, and I commit that I will in fact appoint and pick a woman as vice president.”
Mr Sanders said he would “in all likelihood” pick a woman too.
The debate came ahead of Tuesday’s nominating contests in the big states of Ohio, Illinois, Florida and Arizona, where another string of Biden victories would give him a nearly unassailable lead in delegates.