The Trump campaign has been videotaping voters in Philadelphia as they drop off their ballots.  

A lawyer for the campaign made a formal complaint to officials on Oct. 16, saying a campaign representative had surveilled voters depositing two or three ballots at dropbox. She called the conduct a “blatant violation of the Pennsylvania election code.

The New York Times first reported the development Thursday evening.

“This must be stopped,” Linda A. Kerns wrote in the letter shared with The Hill. She added that the actions “undermine the integrity of the voting process.” 

Kerns wrote that a video taken by a campaign representative shows three people dropping off up to three ballots on Oct. 14. Kerns said that Pennsylvania law requires voters to deliver their own mail-in ballots, although there are exceptions for voters with disabilities. 

Kerns demanded that the city turn over the names of all voters who used a drop box in front of Philadelphia’s City Hall on Oct. 14, and insisted that the city place a staff member around every drop box “at all times.” 

She also asked for footage from areas around City Hall, and that the ballots be set aside “until an investigation can determine whether the ballots were personally delivered” by the voters.

Benjamin Field, a lawyer for the city, rejected her claims, saying that third-party delivery is permitted in certain instances. 

“The Board cannot agree with your conclusion on the basis of the information you provided,” Field wrote according to The Times. "Nor can the Board, in exercising its duties, assume that an individual is violating the Election Code when that person can act as an agent for a voter who required assistance.”

Pennsylvania attorney general Josh Shapiro told the Times that Pennsylvania law permits poll watchers to carry out “very discrete and specific duties,” and that videotaping voters is not one of them. 

“Our entire system of voting is built on your ballot being private and your choice to vote being a personal one,” Shapiro said. “Depending on the circumstance, the act of photographing or recording a voter casting a ballot could be voter intimidation — which is illegal.”

The Trump campaign said it was wrong to suggest their actions represented voter intimidation.

“It is categorically absurd to say that filming a drop box—especially when news outlets do the same—is voter intimidation," Trump campaign spokesperson Thea McDonald said in a statement to The Hill. "It is the height of hypocrisy that Democrats and the mainstream media first claim there is zero evidence of illegal voting, then cry foul when Republicans transparently provide evidence.”

Mail-in ballots have become a contentious issue and has led to accusations of widespread voter fraud as many are hesitant to vote in person because of the coronavirus pandemic. As for Pennsylvania, the state is facing several lawsuits, including from President Trump’s campaign, over how the election is being conducted.

A USA-Today Suffolk University poll released Wednesday found that Trump is trailing Democratic presidential nominee Joe Biden by 7 points in the hotly-contested battleground state.