Abdul Razak Ali Artan was fatally shot by a university police officer when he refused to drop his knife during Monday's attack. Those who knew him say he always said hello to his neighbors in the low-rent apartment complex where he lived with his mother and siblings on the city's west side.
The 18-year-old stopped in frequently at a nearby convenience store for snacks and attended a local mosque.
He had graduated with honors from Columbus State Community College last May, earning an associate of arts degree. A video of his graduation ceremony shows him jumping and spinning onto the stage and smiling broadly, drawing laughs, cheers and smiles from graduates and faculty members.
He transferred to Ohio State to get his bachelor's degree and gave an interview to the university's student newspaper in August, saying he was looking for a place to pray openly and worried how he would be received.
Yet leaders of the mosque say they don't remember Artan, and Ohio State's Muslim and Somali student groups say he wasn't affiliated with their organizations.
"None of us could recognize his face," said Horsed Noah, director of the Abubakar Assiddiq Islamic Center, a mosque around the corner from Artan's apartment.
Artan was not known to FBI counterterrorism authorities before Monday's rampage, Angela Byers, the FBI's special agent in charge in Cincinnati, said Wednesday.
On the day of Monday's attack, Artan got ready to attend classes as always, even dropping his young siblings off at their school first.
"He woke up and he went to school," said Hassan Omar, a Somali community leader who spoke with Artan's mother Monday, hours after the attack.
The first time she knew something was wrong, Omar said, was when police showed up at her doorstep.
Sometime that morning, Artan bought a knife at a nearby Wal-Mart - authorities don't know yet whether it was the one used in the attack - and posted a series of Facebook rants showing he nursed grievances against the U.S., according to Columbus police and the FBI speaking at a Wednesday news conference.
After arriving on campus, Artan drove his car over a curb and into a crowd of people, then got out and started slashing at people with a knife. He was shot to death almost immediately by an Ohio State officer after refusing to drop the weapon, according to the university.
In those Facebook posts, Artan railed against U.S. intervention in Muslim lands and warned, "If you want us Muslims to stop carrying lone wolf attacks, then make peace" with the Islamic State group.
Artan came to the U.S. in 2014 as the child of a refugee. He had been living in Pakistan from 2007 to 2014, according to a law enforcement official. It's not uncommon for refugees to go to a third-party country before being permanently resettled.
Woodyard told the Texas television station KXAS that the Somali family arrived at Dallas-Fort Worth International Airport from Pakistan through New York's Kennedy Airport.
The organization gave the family shelter and aid as part of the government resettlement program, he said. The group's records show the family received shelter for 23 days before leaving for Ohio.
Columbus has the second largest Somali population in the U.S. after the Twin Cities.
President-elect Donald Trump tweeted Wednesday that Artan "should not have been in our country."
Authorities say that Artan and his family were thoroughly vetted before coming to the U.S., and that Artan underwent a second background check when he became a legal permanent resident in 2015.
Columbus State said he had no behavioral or disciplinary problems while he was there from the fall of 2014 until this past summer.
He started at Ohio State in August as a business student studying logistics management.
He was personable and willing to be interviewed and photographed, said Ohio State student reporter Kevin Stankiewicz.
Jack Ouham, owner of a market near Artan's apartment, saw Artan almost every day when he stopped in for snacks but never alcohol or cigarettes.
He was never angry, Ouham said.
"Very nice guy," he said.
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