A man crossing the street against a red light was struck and badly injured early Sunday, police said.
The crash happened just after 3:30 a.m. at First Avenue N and Fourth Street.
Police said that Justin J. Stewart, 22, of St. Petersburg was driving a Nissan Sentra south on Fourth Street N. He had a green light at the intersection, and police said he was traveling at or near the speed limit of 30 mph.
A pedestrian, James T. Legg, 55, who police said is homeless, was crossing Fourth Street against a light and was struck.
He was taken to Bayfront Health St. Petersburg with what authorities described as life-threatening injuries.
The crash remained under investigation.