San Francisco resident Willy Caine Jr., 24, was found fatally shot at 3:07 a.m. Monday in the first block of Brookdale Avenue in The City's Sunnydale neighborhood, police said.
Around 9:30 a.m., San Francisco resident Keith Zinn, 30, was found shot in the first block of Ironwood Way near Jennings Street in Hunters Point, police said.
Zinn was transported to San Francisco General Hospital, where he was pronounced dead, police said.
San Francisco police are also investigating two other fatal shootings that occurred in the city since the Fourth of July.
Around 10 p.m. Friday, 49-year-old Wesley Willis was shot while sitting in a car near the intersection of Harbor Road and Ingalls Street in Hunters Point.
He was taken to San Francisco General Hospital, where he was pronounced dead, police said.
The second fatal shooting was reported at 2:54 a.m. Sunday in the 1700 block of La Salle Avenue in the Bayview.
The victim, Antonio Cortez, 37, was standing with a 49-year-old man in front of a home when someone opened fire at them, police said.
Cortez was pronounced dead at the hospital later that morning. The 49-year-old man was also hospitalized with life-threatening injuries, according to police.
Police said no information was immediately available about suspects in any of the four homicides.
Anyone with information about the killings is asked to call the Police Department's homicide detail at (415) 553-1145. People can also call an anonymous tip line at (415) 575-4444 or send a tip by text message to TIP411 with "SFPD" in the message.