The shooting was reported at about 9:20 a.m. in the 200 block of East 12th Street, police said.
Two victims transported themselves to a nearby hospital, police said. Information on their conditions was not immediately available.
The Dewey Academy continuation school was locked down for about an hour after the shooting, but no one at the school was injured, Oakland schools spokesman Troy Flint said.
Flint said the shooting didn't have anything to do with the school, located at 1111 Second Ave., near East 12th Street. He said the school was locked down from about 9:30 a.m. to 10:30 a.m. as a precaution.
Flint said Oakland Unified School District police were told by Oakland police that the shooting stemmed from a road rage incident.
Monica Winn, administrator of the J L Richard Terrace retirement home at 250 E. 12th St., said there are nine bullet holes in their building from the shooting, and the gunfire narrowly missed a man and woman sitting in the lobby.
"We all are shaken up," Winn said. "We all had to duck for cover and crawl on the floor.
She said police remained at the 80-unit retirement home as of 11:30 a.m. to investigate the shooting.
Family members of the people living at the home tried to get in to see their loved ones but "it's all taped off" due to the investigation, Winn said. "No one can get in or out."