Nov. 1 (UPI) -- The man accused of driving a truck onto a bicycle path and killing eight people was charged with federal terrorism crimes Wednesday, court documents filed in Manhattan indicate.
Local and federal authorities said the attack was "carried out in the name of" the Islamic State near the World Trade Center in Lower Manhattan.
The attack killed eight people and injured others Tuesday, in what officials say is the city's deadliest terror attack since Sept. 11. It unfolded a man ran a rented pickup truck into bicyclists and pedestrians before crashing into the back of a school bus. Authorities said he emerged from the vehicle shouting "God is Great" in Arabic -- and ran down the street waving fake firearms.
Nine people remained hospitalized Wednesday.
A New York City police officer shot and arrested Saipov. They disclosed Wednesday morning that Saipov planned the attack for weeks and carried it out "in the name of [the Islamic State]," NYPD deputy commissioner John Miller said.
Miller said police found a note near the crash scene that promoted the Islamic State -- and added that Saipov planned the attack with instructions from the militant Islamist organization.
The FBI on Wednesday said it is searching for information on another man, Mukhammadzoir Kadirov, 32.
Saipov, 29, is an immigrant from Uzbekistan who arrived in the United States in 2010. He's lived in Tampa, Fla., and Paterson, N.J., police said.
On Wednesday, Cuomo told CBS News the note reinforced Saipov's dedication to the Islamic State.
Cuomo added that there is no evidence to suggest "a wider plot" of terrorism, but added that New Yorkers should expect increased security.
"This was an act of terror, and a particularly cowardly act of terror aimed at innocent civilians, aimed at people going about their lives who had no idea what was about to hit them," New York City Mayor Bill de Blasio said Tuesday.
"Under the Law of War, an enemy combatant can be held and questioned for intelligence gathering purposes without a lawyer present," he said. "Intelligence gathering is an important tool in disrupting and preventing future attacks.
"One thing I like about President Trump is he understands we're in a religious war. We're fighting people who are compelled by their religious views to kill us all."
White House press secretary Sarah Sanders told reporters Wednesday the administration considers Saipov, though he has not officially been designated as such.
Federal law allows enemy combatants to be held by the government without access to an attorney.
NYPD Chief Carlos Gomez, speaking on Wednesday, noted that the city's annual Halloween parade and party, which was held near the scene of the attack and typically attracts up to 1 million people, went on as scheduled. He added that New Yorkers should expect to see an expanded police presence in the next several days, and that Sunday's New York City Marathon, which runs through all five boroughs of the city and attracts more than 2 million spectators, will go as planned.
Five of the dead were from Argentina and were in the city to celebrate a 30th school graduation anniversary, Argentina's foreign affairs ministry said. Another victim was Belgian.
A former neighbor of Saipov's in Florida, Kobiljon Matkarove, told NBC News that the suspect "is no terrorist."
"He was a very happy guy," he said, noting that Saipov is a truck driver and married with three children.
Wednesday morning Trump linked the attack with U.S. immigration policy.
"The terrorist came into our country through what is called the 'Diversity Visa Lottery Program,' a [New York Sen.] Chuck Schumer beauty. I want merit based," he tweeted.
"We will stop this craziness!"
The FBI and New York City Police Department issued a call seeking anyone with images or video that could be useful in the investigation.
In a letter to Trump Wednesday, Uzbekistan President Shavkat Mirziyoyev called the attack "a ruthless and an extremely violent crime." He added that Uzbekistan is ready to assist in the investigation.