Authorities had accused Trevor Bickford, who was 19 at the time of the incident, of plotting what U.S. Attorney General Merrick Garland called a "jihad-inspired attack targeting U.S. government officials."
Prosecutors said Bickford, who lived in Maine, had considered traveling to Afghanistan to fight alongside the Taliban before carrying out the attack shortly before midnight on Dec. 31, 2022, outside a secure area set up for the city's massive New Year's celebration in Times Square in Manhattan.
The officers all survived. Bickford was shot in the shoulder by police before being taken into custody.
He pleaded guilty to three counts of attempted murder and three counts of assault and is scheduled for sentencing in April, court records showed.
Bickford's court-appointed defense lawyers did not immediately respond to a request for comment.
The FBI interviewed Bickford in December before his attack after his mother reported concerns that he had started to become radicalized. He was placed on the federal "no-fly" list to prevent him from traveling overseas.
Bickford also faces separate state charges in connection with the attack.
(Reporting by Joseph Ax; Editing by Leslie Adler)
By Joseph Ax
