WASHINGTON — A 35-year-old Queens man pleaded guilty on Thursday to threatening to kill a congressional staff member and making more than 12,000 harassing phone calls to members of Congress over a less-than-two-year period.

Ade Salim Lilly pleaded guilty to threatening to kidnap or injure someone on interstate commerce as well as making repeated harassing telephone calls. The 12,000-plus calls, more than 6,526 of which targeted congressional offices in Washington, D.C., were made to the offices of 54 members of Congress between February 2022 and November 2023, when Lilly was arrested, according to court records.

Lilly, who has been in custody since his arrest, pleaded guilty before U.S. District Judge Timothy Kelly, who set a sentencing hearing for Aug. 28 at 2 p.m. ET.

Plea documents say that Lilly’s calls were answered by staff members and interns for members of Congress and that he “would become angry and use vulgar and harassing language” toward those who answered the phone.

“Based upon his harassing communication, Defendant Lilly was repeatedly asked by Congressional staff members to refrain from calling,” his agreed-upon statement of offense reads. “In addition, police officers of the United States Capitol Police informed Defendant Lilly on multiple occasions that his phone calls were unwanted, and due to a harassing nature, were prohibited by law.”

In one instance on Oct. 21, 2022, Lilly told a congressional staffer: “I will kill you, I am going to run you over, I will kill you with a bomb or grenade.”

Some staffers would “cease answering their phone” because of Lilly’s insistent calls, court documents said, including when he targeted one office more than 500 times.

The U.S. Capitol Police did not immediately respond to a request for additional details on the calls.