Evidence from the voter registration application fraud cases has stunned Pennsylvania over the past week, leading all the way to Arizona in a private for-profit industry that tries to register voters across counties and has increasingly raised legal concerns.

As counties in Pennsylvania have investigated fraudulent voter applications in recent weeks, one group from Arizona has been of particular interest as it works out of Lancaster County, which is home to a large Amish population that both political parties have courted leading up to the presidential election.

Five Pennsylvania counties are investigating possible fraudulent voter applications and mail-in ballot applications in the days and weeks leading up to Election Day.

The Pennsylvania attorney general’s office announced Thursday, “Apparent attempts to submit fraudulent voter registration forms in Berks, Lancaster, Monroe, and York counties have been defeated. The Office of Attorney General is working with the respective county officials to investigate those responsible for this conduct.”

Additionally, Cambria County has found fraudulent voter registration applications. On Tuesday, Monroe County District Attorney Mike Mancuso announced that about 30 irregular voter applications and mail-in ballot request forms are being investigated by his office, with several of them "found to be fraudulent." One applicant was deceased and several forms were from one person.

"A company calling itself 'Field and Media Corps' a subsidiary of Fieldcorps, an Arizona based organization, working out of Lancaster County, in turn was responsible for submitting the forms in question to county officials," Mancuso said .

The CEO of Field+Media Corps is Francisco Heredia , a city councilman and vice mayor of Mesa, Ariz., in Maricopa County. Heredia previously served as the community relations manager in the Maricopa County recorder's office and worked at the left-wing voting rights group Mi Familia Vota.

Heredia didn’t immediately respond to a request for comment on Friday.

FieldCorps, the parent company of Field+Media Corps, received $200,000 from Mi Familia Vota in June. FieldCorps has worked with Democratic candidates and other left-wing groups.

York County is also investigating a large delivery it received of voter registration forms and mail-in ballot applications.

York County Chief Clerk Greg Monskie told Votebeat on Wednesday that Field+Media Corps submitted the forms that are under investigation. Monskie explained that Field+Media Corps received the forms from the national voter registration nonprofit Everybody Votes campaign.

Everybody Votes told Votebeat that it had not been contacted by the counties of Lancaster, Monroe, or York regarding ongoing investigations, but that it would help resolve any issues with forms if contacted. ”Our partners work diligently to ensure all forms collected comply with all rules and regulations,” Everybody Votes said in a statement.

York County said that of the 3,087 voter registration applications it is reviewing, about 47% of them were verified and approved; about 29% had incomplete information, which requires additional information from applicants before approval; and about 24% were declined and are receiving further review, 85% of which were duplicate requests.

Heredia told Votebeat that Field+Media Corps has not been contacted by Pennsylvania county officials or informed about issues with forms the company submitted. He said that Field+Media Corps will cooperate with any Pennsylvania investigation.

Field+Media Corps has also conducted voter registration drives in Arizona. Richie Taylor, the spokesperson for the Arizona attorney general’s office, told Votebeat that the office received voter registration forms from Field+Media Corps that were flagged for investigation by the counties of Mohave and Navajo last year. The Maricopa County attorney’s office led the investigation.

Heredia said that the Maricopa County attorney’s office contacted Field+Media Corps last year in relation to an investigation into two canvassers employed by the company. The two canvassers were fired.

Heredia explained that Field+Media Corps trains employees to accurately fill out forms and said that the company has a zero-tolerance policy for workers submitting fraudulent forms.

A spokesperson for the Maricopa County recorder's office said Wednesday that FieldCorps has been flagged for a high percentage of inaccurate or incomplete forms that have been submitted.

The campaign for former President Donald Trump and Republican National Committee released a statement on Friday regarding Field+Media Corps.

"Pennsylvania authorities are investigating an alleged fraudulent voter registration scheme and named a radical leftist consulting group, Field+Media Corps, as the organization submitting fraudulent registration forms. These announced investigations raise serious questions: Who is funding these efforts? Is the group active in other states? Is there any connection to leftist dark money groups? These are serious allegations that deserve an immediate and robust investigation to determine if laws were broken. If so, those responsible must be prosecuted to the fullest extent of the law," the statement continued .

"The RNC Election Integrity team is closely monitoring these investigations. The most important election in the history of our country is four days away. These investigations must be done immediately so Pennsylvanians - and Americans across the country - can have faith in the process and confidence in the results. Voters deserve transparency and accountability in our elections."

Meanwhile, in Lancaster County, Pa., prosecutors said last Friday they had uncovered a large-scale scheme to submit fraudulent voter applications that were collected at shopping malls and other locations. Lancaster County District Attorney Heather Adams told a news conference that detectives have found about 60% of some 2,500 voter registrations submitted in recent days to the county's election office were fraudulent.

Adams added that she was aware of at least two other counties that may have similar concerns about recent voter registration applications dropped off in large batches.

In response to a request for comment, the Lancaster County district attorney’s office shared the joint statement from the county district attorney and Board of Elections and stated, "As the District Attorney noted during the press conference, she will not be sharing any details on the actors at this time as it is still an ongoing criminal investigation."

Cambria County, Pa., also rejected 21 voter registration applications earlier last month after the district attorney’s office investigated and found them to be fraudulent. The applications were submitted by a group after a voter registration event, but the name of the group was undisclosed.

Third-party registration organizations have particularly been an election integrity concern.

The Honest Elections Project (HEP) released a report in January on 14 election reforms that states should make to protect the integrity of elections. One of the recommended reforms is “Protect the integrity of the voter registration process.”

“Voters should be able to trust that voter registration groups will properly handle their registrations and personal information,” the report reads . “States should establish standards for the handling and prompt return of voter registration applications, require groups engaged in voter registration drives (VRDs) to complete official training, and register with the state."

“Procedures should be put in place to sanction VRD organizations that repeatedly or intentionally produce inaccurate or incomplete voter registrations, or otherwise violate election laws. Compensation for voter registration activities on the basis of a quota or per registration should be prohibited,” the report continued.

HEP Vice President Chad Ennis told Just the News on Friday that third-party voter registration organizations are a “problem for a lot of reasons,” from committing fraud by inventing fake people to making mistakes on voter registration applications. Voter registration applications are “sent to the wrong place or not sent at all, depending on how the collectors paid,” Ennis said. “Sometimes they just get a name and signature” on the applications, and they “don't make it into the voter registration office.”

Some states allow workers to be paid per voter registration application, “so they have an incentive to pump out as many as they can,” Ennis said, which is “not a great thing when trying to keep voter rolls clean.”