"That's unacceptable," he said. He said some of the Trump observers "clearly don't know what they are doing".
Tim Posnanski, a county election commissioner, told his fellow commissioners there appeared to be two Trump representatives at some tables where tabulators were counting ballots, violating rules that call for one observer from each campaign per table.
Posnanski said some Trump representatives seemed to be posing as independents.
At one recount table, a Trump observer objected to every ballot that tabulators pulled from a bag simply because they were folded, election officials told the panel.
Posnanski called it "prima facie evidence of bad faith by the Trump campaign". He added later: "I want to know what is going on and why there continues to be obstruction."
Joe Voiland, a lawyer speaking to commission members on behalf of the Trump campaign, denied his side was acting in bad faith.
"I want to get to the point of dialling everything down … and not yelling at each other," Voiland said.
At least one Trump observer was escorted out of the building by sheriff's deputies Saturday after pushing an election official who had lifted her coat from an observer chair. Another Trump observer was removed on Friday for not wearing a face mask properly as required.
Trump paid $3 million, as required by state law, for the partial recount that began on Friday and must conclude by December 1.
His team is seeking to disqualify ballots where election clerks filled in missing address information on the certification envelope where the ballot is inserted, even though the practice has long been accepted in Wisconsin.
The campaign also alleges thousands of absentee ballots don't have proper written paperwork, and that some absentee voters improperly declared themselves "indefinitely confined," a status that allows them to receive a ballot without photo ID. Those challenges were being rejected.
There have been at least 31 recounts in statewide elections in the US since the most famous one in Florida's presidential election in 2000.
The recounts changed the outcome of three races. All three were decided by hundreds of votes, not thousands.