Democratic Party chairman Tom Perez has been accused of “exposing people to coronavirus”, after primary elections proceeded with in-person voting in three states.

Four states were due to hold ballots to help decide a nominee to take on Donald Trump in November – Florida, Ohio, Arizona and Illinois.

Ohio’s governor managed to secure a postponement of his state’s vote, concerned that both voters and poll workers were putting themselves at risk. Some voting rights activists have filed legal actions in places such as Florida, calling for the voting by post deadline to be extended to ensure people can cast a ballot without endangering themselves.

Voting proceeded in Florida, Arizona and Illinois, with workers wearing rubber gloves and making widespread use of hand sanitiser. Some people chose to vote wearing masks.

Louisiana, Georgia Kentucky have already postponed their votes.

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On social media, Mr Perez was attacked for potentially exposing people to coronavirus, even though he said it was up to individual states to decide whether to proceed.

“Reports coming in from IL primary are mind-bogglingly bad: voters being turned away from understaffed polls in droves, totally unsanitary conditions, elderly at extreme risk,” tweeted Thea Riofrancos, a writer and political scientist based in Rhode Island.

“Meanwhile Tom Perez and DNC are scrambling to save face. Shows you exactly what their priorities are.”

A person tweeting under the handle Rebecca Pearl and apparently working at the Illinois primary, tweeted a long thread claiming to have no cleaning supplies, or the correct ballot equipment.

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She wrote: “Election Day so far: 5/8 election staff are elderly, we were provided with no cleaning supplies, we are missing an ENTIRE blue box (meaning anyone who comes to this precinct cannot vote), we are missing 2 election judges & nobody is answering our calls..”

Cynthia Nixon, the actress who in 2018, unsuccessfully ran to be governor of New York, tweeted: “I don’t understand why anyone besides a health expert in pandemics is deciding whether states should be voting in person tomorrow. Who cares what @TomPerez thinks?”

Anger was also triggered after it was reported the DNC was planning to inform states looking to delay their primaries behind June that they could lose half of their delegates. The Guardian said that reduction wold as much as 50 per cent.

On Monday evening, as Mr DeWine pushed to halt voting in Ohio, Mr Perez was asked about the wisdom of allowing the primaries to proceed.

“Yes, we respect what they’re doing,” Mr Perez told MSNBC. “I don’t think it’s for me to second-guess those judgments of governors who insisted they are able to safely carry on with the primaries.”

He also said he supported more mail-in primaries. He said: “Wherever practicable, and I think you can make this happen.”