According to Travis Rice, a reporter for Fox News in LA, two of the shooting victims were killed and about 500 people were present.
No one has been arrested yet.
Mr Rice tweeted: “JUST IN: Two killed in Peck Park shooting in San Pedro.
“According to LAFD, there were about 500 people in the park when it happened. Seven shootings.
“LAPD says they are investigating this as multiple shooters. No one in custody.”
According to officials and witnesses, multiple gunmen opened fire in the park, injuring at least seven people.
Officers were called to assist an active gunman at the park at 3:51 p.m. on Sunday, and officials have now added they believe multiple gunmen were involved in a gang-related incident.
Los Angeles Fire Department spokesman Brian Humphrey said at least four men and three women were shot and taken to nearby hospitals.
He added that at least one of the men and one of the women were in critical condition and that the incident happened near a car show at the park.
The fire service said: “At least three of the patients have been confirmed to have suffered gunshot wounds, including a man and a woman, both transported in critical condition.
“There are no other patients on site. The circumstances of the incident, the patient’s demographics, the relationship and the exact nature of each patient’s injuries are yet to be confirmed.”
A dispatcher described the incident, saying that “the entire park is a crime scene,” after witnesses described hearing dozens of shots.
No arrests have been made yet and the city has been tactically warned by the LAPD throughout the city due to the large number of officers on the scene.
The LA Police Department’s official Twitter account tweeted: “About 3:50 p.m., Harbor Division agents responded to 911 calls of a multi-victim shooting in Peck Park.
“NO active shooting situation. PIO is on its way.”
According to CBS News, an LAPD officer was spotted performing CPR on a male victim at the scene in San Pedro.
According to LAPD officers at the scene, while the entire park is currently being treated as a crime scene, all those present during the shooting are reportedly not allowed to leave until police can release them as suspects.
LAPD Captain Kelly Muniz said, “We don’t know how many gunmen we have right now.”
Captain Muniz added that the shooting was a dispute between two parties and that weapons were recovered at the scene.
Officer Garcia said the park had been closed by police and people were being returned to their vehicles to clear the area.
At 6:45 pm local time, a number of police officers in bulletproof vests and helmets arrived with some rifles.
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