The suspect was the only one killed. Nobody inside the Nazareth restaurant and deli said they knew him, according to police.
"(He) immediately began swinging a machete at customers and employees inside," Columbus police Sgt. Rich Weiner said. "There was no rhyme or reason as to who he was going after as soon as he walked in, according to some of the witnesses."
Police have tentatively identified the suspect but would not reveal his name or age.
"Right now there's nothing that leads us to believe that this is anything but just a random attack," Weiner said.
Karen Bass was inside the restaurant when it all happened.
"He came through the front door and then started just systematically hitting people," she told CNN affiliate WSYX
. "I thought it was a personal thing, and then he just started down the row hitting everybody."
Four people were injured and transported to the hospital.
One victim who was in critical condition underwent surgery and is now "stable," Weiner said.
The suspect was seen 30 to 45 minutes earlier entering the restaurant and speaking with an employee. Police would not discuss details of that conversation.
He left, came back at around 6 p.m. and then attacked a man and woman at a booth just inside the door, Weiner said.
Two men immediately ran out and called 911 while another engaged in a "physical altercation" with the suspect. Some patrons started throwing chairs.
An employee then "grabbed something from behind the register" and stopped the attack, according to Weiner.
"There's blood all over inside the restaurant," Steven Bass, Karen's husband, told WSYX.
Witnesses were able to give authorities enough information about the suspect's vehicle that another officer spotted it soon after, and a chase began.
Once authorities were able to get the suspect off the road, he tried to exit from the passenger side of the vehicle and an officer unsuccessfully tried to use a stun gun on him, Weiner said.
The suspect eventually made it out of the vehicle with a machete and another knife in hand.
Then, "he lunged across the hood at the officers," Weiner said. "Another officer in a cruiser fired a couple shots at him and put him down."
The FBI is helping local police with the investigation, which includes trying to determine the attacker's motive, a U.S. law enforcement official said on condition of anonymity.