The suspect in Monday's attack at Ohio State University rammed into pedestrians with a car and attacked them with a butcher knife, before being shot dead by police, officials said.

"About 9:52 am, a male suspect drove a vehicle over the curb... struck pedestrians," Craig Stone, chief of police at the university, told a news conference.

"He exited the vehicle, and used a butcher knife to start cutting pedestrians."

"Our officer was on scene in less than a minute and he ended the situation in less than a minute. He engaged the suspect, and he eliminated the threat," Stone added.