Police and emergency crews have descended on Lambeau Field in Green Bay.
The Press-Gazette said agencies that responded to the stadium include the Brown County Sheriff's Office, Wisconsin State Patrol, Green Bay Police Department and the Green Bay Metro Fire Department.
According to police, the suspect is an Asian male who is about 20 years old and lives in Green Bay.
Police said that last month the suspect fought with the former co-worker he tried to run down, which caused him to lose his job.
Two people who work in the stadium said they were told a man driving a vehicle hit one auto that became wedged beneath a minivan. No weapon was found and no shots were fired, police said.
ABC affiliate WBAY said that a former employee of a company providing food services at the stadium rammed his vehicle into a auto in the parking lot, chased a victim and drove into a storage area in the stadium. WBAY tweeted a photo of a minivan resting atop another vehicle in a parking lot outside the Packers' training facility.
On Saturday, Lambeau Field will be the scene of the Vikings-Packers Week 16 game.