03/11/2017 9:17 PM AEDT | Updated 03/11/2017 9:39 PM AEDT

ISIS Claims Responsibility For New York City Terror Attack

The self-described Islamic State militant group claimed responsibility for the terror attack in lower Manhattan this week, which killed eight and injured 12.

ISIS described the attack in its weekly Al-Naba newsletter as "one of the most prominent attacks targeting Crusaders in America," and a response to its call to target "citizens of the Crusader countries involved in the alliance against the Islamic State." The publication also called the alleged assailant, who is in police custody, a "soldier" of the group.

It's a pattern seen before, although the militant group waited longer than it typically does to claim responsibility. ISIS also tends to release the news via its Amaq news agencyafter a flurry of activity among pro-ISIS online accounts.

Police said Wednesday that the suspect, Sayfullo Habibullaevic Saipov, acted in the name of ISIS and had been planning the attack for several weeks. Notes found at the scene point to Saipov's belief that the militant group would "endure forever."

While recovering from a gunshot wound at a hospital in New York, Saipov asked investigators if he could display ISIS flags in his room, according to a complaint released by the U.S. Attorney Southern District of New York. In court papers, prosecutors noted Saipov said "he felt good about what he had done."

The suspect had planned to put ISIS flags on his vehicle but later thought better of it, afraid it would draw attention to him, the complaint said. Saipov's cellphones contained about 90 videos and 3,800 photos, many related to ISIS, The Associated Press reported. The images included ISIS prisoners being beheaded, shot or run over by a tank.

The group's intricate involvement in each attack differs. It is currently unclear to what extent, if any, ISIS was involved in planning or inspiring the attack in New York. It's also rare for ISIS to claim responsibility for an attack if the perpetrator is in custody, New York Times' ISIS correspondent Rukmini Callimachi noted.

Following ISIS's claim of responsibility for the deadly mass shooting in Las Vegas on Oct. 1, which lacked evidence, there has been increased scrutiny over the credibility of the group's statements.

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