Zale H. Thompson attacked four police officers with a hatchet in New York City on Thursday. Courtesy/Reuters

New York City police are still investigating the motives for Zale H. Thompson’s hatchet attack on four officers in Queens on Thursday, but Commissioner Bill Bratton says no evidence is known to tie him to any terrorist organization.

"There is nothing we know of at this time that would indicate that were the case," Bratton said Friday. New York Gov. Andrew Cuomo also said there was no information that Thompson’s attack was terrorist-related.

Police Officer Kenneth Healey is hospitalized, recovering from being struck in the back of the head with a hatchet. Healey, 25, was on duty with three fellow cops when Thompson charged at them with a hatchet on Thursday.

Another officer, Joseph Meeker, 24, was struck in the right arm. The other two NYPD officers fired at Thompson, killing him. One of the stray bullets struck a nearby pedestrian, hitting her in the lower back. She is currently in the hospital recovering from surgery.

"Here are four rookie cops, just starting out in their career, when the absolute unexpected happened," Mayor Bill de Blasio said during a press conference on Thursday. "They responded exactly as their training dictated and ended the situation -- thank God -- very, very quickly. "

Law enforcement officials say Thompson was hiding behind a bus shelter, waiting to attack the officers. Thompson had a criminal record in California and had been discharged from the Navy for misconduct, a law enforcement official said.