The 29-year-old man detained after a flatbed truck zoomed down a popular lower Manhattan bike path, killing at least 8 people and injuring more than a dozen more, left a note in the truck claiming he committed the attack for ISIS, according to law enforcement sources.

Authorities said the man, identified by sources as Sayfullo Habibullaevic Saipov, is thought to be a “lone actor” in the attack in the Hudson River Greenway on Tuesday afternoon. Authorities said he shouted “Allahu Akbar” at some point as he drove down the bike path and apparently deliberately rammed into a school bus for children with disabilities.

The Uzbek national living in New Jersey got out of that truck afterward and was seen running through traffic on West Street with a BB gun and a paintball gun before being shot in the abdomen by police and taken into custody. He’s being treated at Bellevue Hospital, where he remains in custody.

While Saipov allegedly wrote in the note he committed the act for ISIS, U.S. intelligence officials said they had no knowledge of any terror groups claiming responsibility for the violence. Gov. Cuomo said that Saipov is thought to have acted alone in the attack.

Sources said Saipov lives in Paterson, New Jersey, but he had a Florida license with a Tampa address on him when he was arrested. Police and federal agents were seen swarming the neighborhood street where he lived on Tuesday night as well as the Passaic Home Depot where he rented the flat bed truck and left his family minivan.

Residents in the area said that Saipov had a wife and two young children and that they had lived in the home on and off for about three years. Fellow Muslims in the neighborhood said that while he and his wife appeared to be practicing the faith, they only saw him at the local mosque once or twice.

We are not like him,” said Mohammed Ghaith, who goes to the mosque. “Not harmful or anything like that. I don’t know what he’s been through or what he went through but we should all be like peace.”

Kobiljon Matkarov, a Facebook friend of Saipov’s, told NBC News that the two met while they were both living in Florida. He said his friend was working as a truck and Uber driver.

“He was very happy guy,” said Matkarov, who is also from Uzbekistan. “he liked the US. he is no terrorist. He’s all the time happy, smiling all the time.”

Saipov also pleaded guilty to two traffic offenses in Pennsylvania between 2012 and 2015, according to records from the Keystone State. He was also arrested for failing to appear in court after getting another traffic citation in Missouri in 2015; he later paid a fine and served no jail time. It’s not clear if he had any other criminal history beyond the traffic offenses.

Anyone with information on Saipov or the attack is asked to call Crime Stoppers at 1-800-577-TIPS or the FBI’s tips hotline at 1-800-CALL-FBI.