A Brooklyn volunteer neighborhood safety patrol member pleaded guilty on Wednesday to bribing police officers to expedite gun license applications, becoming the latest person to admit wrongdoing in a wide-ranging corruption probe in New York City.

Alex Lichtenstein, a member of an Orthodox Jewish neighborhood patrol group, told a federal judge in Manhattan that he paid the bribes to New York police officers in charge of approving gun permits between 2013 and 2016.

"During these years I gave police officers in the Licensing Division things of value including money knowing that by giving them these things the officers would do me favors," a trembling Lichtenstein said before U.S. District Judge Sidney Stein.

Wearing a dark suit, open-collared white shirt and black yarmulke, Lichtenstein, 45, pleaded guilty to one count of bribery and one count of offering a bribe.

Under a plea deal, he agreed not to appeal any prison sentence of 71 months or less and forfeit $230,000. His sentencing is scheduled for March 16.

Lichtenstein was arrested in April as part of a wide-ranging corruption investigation that has resulted in several police officers being charged or disciplined, and put the fundraising of New York City Mayor Bill de Blasio under scrutiny.

At least three people have pleaded guilty, including Jona Rechnitz, a real estate investor who secretly pleaded guilty and agreed to cooperate with investigators, a person familiar with the matter previously told Reuters.

Rechnitz has been central to the investigation along with another businessman, Jeremy Reichberg, who was charged in June as part of the bribery probe.

Both served on de Blasio's inaugural committee after his 2013 election and either raised money for his campaign or for a nonprofit organization set up to advance his agenda. De Blasio has not been charged with any wrongdoing and has said he and his administration have acted legally.

In Lichtenstein's case, prosecutors said he charged his clients as much as $18,000 to expedite gun license applications.

They said he offered to pay one police officer $6,000 per license application while boasting that he had secured licenses for 150 people in the past. The officer reported the incident to the police department's internal affairs division.

When asked by reporters after the hearing if he was cooperating with the government in providing information on others, Lichtenstein shook his head and replied: "No, no, no." His lawyer declined further comment.