Suspect charged in New Year's Eve machete attack on police officers near Times Square

The 19-year-old accused of attacking three police officers with a machete on New Year's Eve near Times Square has been charged with two counts of attempted murder of a police officer and two counts of attempted assault.

Trevor Bickford, from Wells, Maine, allegedly attacked the officers unprovoked after taking a train to the city on Dec. 29, 2022. His alleged assault came weeks after the suspect was placed on a federal watchlist that would have prevented him from traveling overseas after his mother informed the FBI about her son's gravitation toward Islamic extremism, law enforcement sources told ABC News.

Police found the suspect's backpack at the scene, which contained a diary, sources said.

The final diary entry indicated the suspect thought he would die in the attack and asked for burial according to Islamic tradition, the sources said.

Bickford has made statements to investigators that strengthen the belief the attack was motivated by Islamic extremism, law enforcement sources told ABC News.

Bickford told police he took a sip of water and shouted "Allahu Akhbar" before attacking the officers with a knife, sources said.

The knife was purchased in Maine, where Bickford also withdrew thousands of dollars in cash at some point before taking Amtrak to New York. The withdrawal and the purchase suggest premeditation, sources said.

The knife was described as rusted and blunt, according to sources. Had it been sharper, the injuries to the officers would likely have been more severe, the sources said.

Last month, Bickford's mother allegedly called the FBI and warned them about his gravitation toward Islamic extremism, according to law enforcement sources. The FBI interviewed Bickford and determined he sought to travel to Afghanistan to fight for the cause, the sources told ABC News on Monday.

Bickford was allegedly placed on a federal watchlist that would have prevented him from traveling overseas, but there was nothing to prevent him from boarding an Amtrak train to New York on Dec. 29, the sources told ABC News.

Upon arrival in New York, the suspect made a large cash donation to the Bowery Mission, which investigators believe was meant to satisfy a Muslim tenet of charity.

From there, it's believed Bickford slept in a park in Forest Park, Queens. Police recovered a sleeping bag linked to the suspect, sources said. Investigators are interested in what brought him to the park in a remote part of the city and whether he intended to meet anyone.

The three officers were released from the hospital on Sunday.

New York Police Commissioner Keechant Sewell reporters during a press conference Sunday that the incident occurred just after 10 p.m. on Saturday near West 52nd Street and Eighth Avenue, outside the secure area that had been set up for New Year's Eve celebrations.

Sewell said the attack was "unprovoked" and that Bickford attempted to strike one officer over the head with the machete.

"The male then struck two additional officers in the head with the machete," she said.

One of the officers fired their weapon, striking the suspect in the shoulder, according to Sewell. The suspect was then taken into custody.

Bickford remains hospitalized in custody at Bellevue Hospital because of the injuries he sustained when police shot him.

One of the injured officers, an eight-year veteran of the NYPD, suffered a laceration to the head, officials said. Another hurt officer had just graduated from the police academy on Friday, and as is traditionally the case, his first assignment was the New Year's Eve detail in Times Square.

The rookie was also struck in the head, resulting in a skull fracture and large laceration, officials said.

Prior to New Year's Eve, the NYPD had noted that terrorist groups had been mobilizing for a potential New Year's Day attack.

"Throughout December, multiple pro-ISIS users disseminated extremist propaganda graphics broadly calling for attacks in advance of the New Year, advocating a wide range of low-tech tactics," the NYPD's pre-event assessment report said.

The FBI's Joint Terrorism Task Force had previously looked into the suspect, law enforcement sources told ABC News, after the reports from his mother and aunt. Federal terrorism charges are still possible in the attack.

ABC News' Mary Kekatos and Ivan Pereira contributed to this report.