TROY — Democratic and Republican private investigators want to know how three allegedly fraudulent signatures ended up on Working Families Party petitions that were turned in by a Democratic committeeman.

“I’ve got nothing to say,” said Anthony Isopo, the Democratic official, when asked about the alleged forgeries in a Wednesday phone call. He then hung up.

The alleged forgeries appeared on petitions for Democratic district attorney candidate Mary Pat Donnelly and Troy Democratic Chairwoman Carole Claren-Weaver, who is running for county legislature.

Republicans recognized there might be forgeries among the five signatures collected by Isopo when they reviewed the petitions. One of the names, Joseph Riley III, was known as a person who would be unlikely to support Mary Pat Donnelly, the Democratic candidate for district attorney.

County Republicans and Democrats are aware of the identities of voters in the minor parties, many of which have ties to the two main parties. The Democrats and Republicans usually battle in every primary to secure the additional minor party lines to gain marginal advantage in the November general elections.

Riley filed specific objections to the petitions late Monday afternoon, complete with affidavits from him and two other people who say they never signed the petitions.

“The existence of these forgeries demonstrates the petition is permeated with fraud and should therefore be disqualified,” Riley wrote in both objections, which were identical except for the candidate's name.

Riley said he signs his name "Joseph" and not "Joe," as it appears on the petition.

Timothy Nelson's affidavit said he didn’t sign the petition, and chalked up the appearance of his signature to "identity theft.” Jennifer Poehlman said she was out of town in Essex County when her name was signed to the petition — at least according to the contested document.

These names account for three of the five signatures submitted by Isopo, who is a Democratic committeeman in Troy’s 2nd Election District. Isopo also collected 20 signatures on Democratic party petitions.

Isopo is a commissioner of deeds appointed by the City Council, a post that allows him to collect signatures for other party petitions. A Republican leader said the party has sent an investigator to the other addresses, but has been unable to contact the voters.

Donnelly said Wednesday that knowing Rensselaer County’s political history, she feared this was an attempt to undercut her campaign message of restoring ethics and integrity to the district attorney’s office.

“I do not know nor have I ever met the individual who carried the petition in question," Donnelly, of East Greenbush, said in a statement Tuesday night. "This individual has never been a member of my campaign committee. I am at a loss to explain why this individual endeavored to commit this apparent act of deceit. In fact, I cannot help but question if it was done as an act of sabotage to sully my reputation and jeopardize my campaign."

Donnelly said she hired a private investigator to look into the matter. She said she has not ruled out filing a criminal complaint.

Republican District Attorney Joel E. Abelove of Rensselaer issued a lengthy statement Wednesday afternoon on his campaign’s Facebook page attacking Donnelly.

"It is unbelievable and unconscionable that in this day and age voters signatures are being forged and the rights of voters stolen," Abelove said.

Abelove called for a probe by the county Board of Elections. As of Wednesday afternoon, the board had not reviewed the contested petitions.

In the County Legislature race, the comments mirrored those in the district attorney's contest. "I didn't know anything about it," Claren-Weaver said.

Legislator Kim Ashe-McPherson, C-Troy, said, "Voter fraud and forgery are serious offenses and the residents whose names were forged deserve justice."

Even if the signatures are disqualified, they do not appear to be enough to lead to the removal of the two Democrats from the Working Families Party line.

Phil Markham, county chairman of the WFP, said the party didn't know who Isopo is. Markham said the party collected enough signatures for the nominating petitions on its own.

The flap harkens back to the 2009 Working Families Party primary, in which scores of voter signatures were forged on absentee ballots for Democratic candidates in Troy. Four Democratic operatives pleaded guilty and two were acquitted in trials.