State Police Chief Craig Stone said the attacker purposely drove over the curb into pedestrians.
The attack, which began around 9:52 a.m., took place in front of Watts Hall, where the Department of Materials Science and Engineering are located, said Monica Moll, of the Ohio State University Department of Public Safety.
Moll said that "injuries were minimized" due to the rapid reaction of campus police.
Injuries included stab wounds and vehicular wounds. It is believed that one person is in critical condition.
The school initially had everyone shelter in place but the all clear was given at around 11:30 a.m. and declared the "scene is now secure."
Jerry Kovacich, a student in welding engineering, told the school paper, The Lantern, that he witnessed a man drive a car into a crowd of people after a fire alarm went off. After the crash, he then saw the man get out of the vehicle and begin attacking bystanders with a knife.
"The guy ended up just coming and hopping the curb with his car and trying to mow down a couple people. He lost control, and I think he ended up hitting three people, and then people were around the car. Somebody asked him if he was OK and the guy just hopped out of the car with a butcher knife and started chasing people around."
The man in the car was tentatively identified as a Somali refugee student and the attack is said to have been planned, but more information is obviously pending.
In fact, as many as 80% of migrants who have fled to Europe claiming to be fleeing the Syrian war, aren't even from Syria.
Another fact: nine of the Islamic jihadists who killed 130 people in Paris last year in November had entered France as refugees.
One IS operative boasted in September 2015, after the influx of migrants began, that among them 4,000 jihadis had already entered Europe. "It is our dream that there should be a caliphate not only in Syria but in all the world, and we will have it soon, inshallah," he said.
We can pretend, at our own peril, that he's lying.