Rep. Rodney Frelinghuysen (R-NJ) exposed one of his constituents as “one of the ringleaders” of a political organization agitating against him in a fundraising letter to her employer last month, according to a report published Monday.

Frelinghuysen warned of “organized forces — both national and local — who are already hard at work to put a stop” to his agenda in a fundraising letter dated Mar. 21 to a board member of a local New Jersey bank, according to a copy obtained by WNYC.

A hand-written postscript to the letter in the same ink as the congressman’s signature noted: “P.S. One of the ringleaders works in your bank!”

According to WNYC, a news article attached to the letter quoted Saily Avelenda, a member of the steering committee of NJ 11th For Change, a nonpartisan group that has pressured Frelinghuysen to hold town hall meetings and stand up to President Donald Trump’s agenda. Avelenda formerly served as senior vice president and assistant general counsel at Lakeland Bank.

Frelinghuysen’s campaign sent the letter to Joseph O’Dowd, a board member at Lakeland Bank, according to the report. O’Dowd donated to the congressman in the current and previous election cycles, according to FEC filings.

Avelenda told WNYC that her employer presented her with the article and letter from Frelinghuysen’s campaign. She said she later resigned from her position at the bank in part because of the pressure she received for her political efforts.

Avelenda said Frelinghuysen “used his name, used his position and used his stationery to try to punish me.”

“I thought my Congressman put them in a situation, and put me in a really bad situation as the constituent,” she told WNYC.

Frelinghuysen’s campaign office did not immediately respond Monday to TPM’s request for comment.

In a written statement to WNYC, his campaign office said Frelinghuysen “wrote a brief and innocuous note at the bottom of a personal letter in regard to information that had been reported in the media.”

The congressman’s Democratic challenger, Mikie Sherrill, is already seizing on the episode. She called the letter a “shameful abuse of power” in a statement.

“Frelinghuysen has gone from simply refusing to meet with his constituents and telling them to ‘back off,’ to threatening constituents who are exercising their freedom of speech,” Sherrill said in the statement. “That Frelinghuysen would use his powerful public office to hurt a private citizen is wrong, unethical and immoral.”