A knife was pulled and a woman stabbed after a crash on the Churchill Roosevelt Highway near Aranguez on Monday.
The fight brought traffic to a halt.
Videos circulated on social media show the two vehicles in a crash, and two men and a woman scrambling across the lanes.
A man is seen with a large knife attempting to stab the other man in the chest as he falls backward, pitching an object out of his hand.
The woman races behind and tackles the man with the knife, who then turns on her and stabs her in the arm.
Her companion beats the armed man on the head with an object until he releases the woman.
Motorists stopped and assisted the injured woman, and were seen on their phones calling for help.
Highway Patrol officers have responded to the incident.