Officers were called to a house located about three blocks south of the Fresno Yosemite International Airport at 7:48 pm on Sunday.
Fresno Police say around 30 people were at the house having a party to watch a football game on television. The gathering was described as peaceful and quiet before the shots rang out.
Investigators say that at least two suspects entered the backyard from the side of the house and opened fire, using semi-automatic pistols, on the 16 men that were in the yard. The people in the yard say they did not see the suspects, only flashes of light from the guns. Because of that, Fresno Police have not been able to provide a description of the suspects.
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The other people inside the home, which included women and children, were not injured.
Fresno Police Chief Andy Hall says the shooters targeted the house but didn't seem to pick out specific victims. He noted some of the members attending the party were linked to a "disturbance" last week, also described as a fight, but was vague on the details of the incident.
Hall was not aware of any connection between the victims and gangs, but he announced a new Asian gang task force, in part, because of the upcoming Hmong holiday that draws thousands to Fresno every year.
"We haven't seen a spike in Asian gang violence in a while. And we're starting to see it now as we're heading into the Hmong new year celebration. We just want to get ahead of it," Hall said.
Hall cited three Asian gang incidents this month and 11 this year, although he wouldn't say there's a direct connection between any of them and the mass shooting Sunday night.
One of the incidents was a homicide Sunday morning, about 14 hours before gunmen targeted the party. Investigators say it also involved two shooters who had a specific target in mind.
"When they opened the door, they entered the residence and held the occupants at gunpoint," Hall said. "It appears they were looking for an individual inside the apartment."
Hall added that the people who lived at the house have been very cooperative, and no weapons were found at the home after the shooting.
On Sunday night, five of the victims were taken to be treated at the trauma center of a hospital in downtown Fresno, and one other was taken to another nearby hospital for treatment. Hospital officials say of the shooting victims, two are in critical condition, three are in critical but stable condition. A bullet grazed another victim.
When officers arrived, they found three people who had already died from their injuries. The fourth victim died at a hospital.
Pao Yang, a Hmong community representative and CEO of The Fresno Center, said that two of the victims are well-known singers in the Hmong community.
The Fresno County Sheriff's Office has identified the victims as 23-year-old Xy Lee, 31-year-old Phia Vang, 38-year-old Kou Xiong, and 40-year-old Kalaxang Thao, all lived in Fresno.
BREAKING NEWS: several police vehicles and multiple ambulances on scene near Lamona & Sandau. pic.twitter.com/U8gGn1sVh9— Gilbert Magallon (@GilbertABC30) November 18, 2019
The federal Bureau of Alcohol, Tobacco, Firearms and Explosives announced late Sunday night that it would be sending agents from its San Francisco field office to assist in the investigation of the shooting.
Breaking: ATF San Francisco Field Division special agents are responding to shooting in Fresno, CA. pic.twitter.com/WO6PLfGR9D— ATF San Francisco (@ATFSanFrancisco) November 18, 2019
Fresno Mayor Lee Brand released a statement in response to the mass shooting:
"My prayers go out to the victims and their families, along with the promise that those responsible for this horrific crime will face the full force of justice. The City of Fresno will not tolerate this type of violence in any of our neighborhoods. We will add whatever resources that are necessary to find those responsible. This senseless tragedy does not define us - rather, our response and unity as a community will and I have complete confidence in our collective resolve."