Sayfullo Saipov, detained after allegedly driving a pick-up truck through a Manhattan bicycle lane on Tuesday and killing eight, demanded an Islamic State (ISIS) flag to display in his hospital room, according to a criminal complaint released on Wednesday.

Authorities said Saipov expressed his allegiance to the terror group and claimed that he “felt good about what he had done.”

He also reportedly told authorities he planned to display an ISIS flag on the truck he used to carry out the attack and asked during his interview whether he could display the caliphate’s flag in his hospital room.

President Donald Trump expressed his anger at the demand, adding that he should be executed:

The 29-year-old Uzbek citizen stands accused of driving a vehicle into civilians in New York on Halloween, killing eight people and injuring at least a dozen others in what was the city’s deadliest attack since 9/11.

“Saipov wanted to kill as many people as he could,” the complaint read:

The suspect said he was inspired to join the caliphate after watching a video featuring ISIS leader Abu Bakr al-Baghdadi’s asking “what Muslims in the United States and elsewhere were doing to respond to the killing of Muslims in Iraq.”

Wednesday morning, police found a note in the truck in which Saipov pledged allegiance to the caliphate, which authorities stated was written in Arabic and proclaimed the immortality of the terrorist group.

Authorities also found about 90 videos and 3,800 images of ISIS propaganda on the suspect’s cell phone, including videos of militants running over a prisoner with a tank, shooting people in the face, and constructing explosive devices.

Saipov appeared in court on Wednesday in a wheelchair; police officer Ryan Nash shot him in the abdomen and detained him when he refused to surrender.

Saipov faces charges of providing material support to the Islamic State, federal terrorism, and the violence and destruction of motor vehicles.

According to reports, Saipov entered the United States eight years ago through the Diversity Visa Lottery program, which secures 50,000 visas every year for foreign nationals from a number of terror-prone countries, including Afghanistan, Egypt, Iraq, Lebanon, Libya, Saudi Arabia, Somalia, Syria, Yemen, and Uzbekistan.

The Islamic State has previously urged “lone wolf” attackers to target tourist hot spots, such as New York, through the use of vehicles or other dangerous weapons.

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