NYC terror suspect pleads not guilty to charges stemming from attack

Sayfullo Saipov, 29, wore shackles in a New York City courthouse Tuesday.

— -- The man accused of using a rented truck to mow down pedestrians in lower Manhattan pleaded not guilty Tuesday to charges stemming from the Halloween terror attack.

Saipov allegedly told authorities he was inspired to carry out the attack by ISIS videos he watched on his phone, according to the indictment.

"He decided to use a truck to inflict maximum damage against civilians," federal prosecutors said.

Saipov, who was shot by police after he crashed into a school bus and fled the truck, requested to hang the ISIS flag in his hospital room and stated that he felt good about his actions, police said. He also stated that he wanted to hang the ISIS flag from the truck, but decided against it because he did not want to draw too much attention, according to the indictment.