"We are still the safest big city in America," Garcetti said during a news conference at the Los Angeles Police Department's Mission Division, where the department started to roll out its use of body cameras for officers earlier in the week.
Thirty-nine people were killed in Los Angeles last month, marking the deadliest August in the city since 2007, when 41 people were slain. Through Saturday, 185 people had been killed in the city this year -- a nearly 7% increase compared with the same period in 2014, according to LAPD data.
Garcetti said the officers going to South L.A. are "good community officers and good tactical officers" who will get out of their cars and walk beats in high-crime areas.
"Those are folks who can actually go to the shot callers and say, 'Hey, can we put gang truces out there, can we look at what's happening and make sure that whatever retribution is going back and forth, we stop it in its tracks?'" he said.
LAPD Chief Charlie Beck said his department's South Bureau had set up a command post that is staffed 20 hours a day and is overseen by a captain or higher-ranking officer to coordinate the response. Officers, he said, are meeting with gang intervention workers, clergy and other community groups to quell the violence.
"They are firing on all cylinders to reduce the problem," Beck said at the news conference.
Meanwhile, community activists called on Garcetti to hold an emergency gang violence summit, which would bring together civil rights leaders, residents, anti-gang violence workers and gang members in an effort to curtail the surge in homicides.
"We need to have a comprehensive murder-and-violence-reduction program by the mayor's office."
Los Angeles Times staff writers Joseph Serna, Kate Mather and Nicole Santa Cruz contributed to this report.