There was a fatal shooting in the Mission District early this morning, and this is now the third death by gun violence in the Mission in less than a month, and the fourth since mid-June.

San Francisco police say they responded just after 5 am Monday to a report of a "physical assault involving a firearm at 20th and Shotwell streets," as KRON4 reports.

Officers arrived at the scene and found a male victim suffering from a gunshot wound.

Police and paramedics performed life-saving measures, but the man was declared dead at the scene.

This is the third fatal shooting in the Mission neighborhood since mid-July, including the fatal shooting at the 16th and Mission BART plaza on July 24. Another shootout involving multiple gunmen left one person dead at 16th and Mission streets two weeks earlier, on July 9.

Monday's homicide was San Francisco's 21st of the year to date.

No arrests have been made.

If anyone has information about the killing, they are asked to call the SFPD at 415-575-4444 or text a tip to TIP411 and begin the message with SFPD.

Photo: Justin Sullivan/Getty Images