Four men were killed and six others shot in what police say was likely a targeted shooting Sunday night at a backyard football watch party in Fresno, California, and authorities are investigating a possible link to Asian gang violence.

Police say some 35 to 40 family and friends were watching a football game in the southeast section of the city when one or more people sneaked onto the property and began shooting. They did not appear to have actually entered the house, Fresno police Deputy Chief Michael Reid told reporters.

“It’s very likely that it was targeted — we just don’t know why,” Reid said. “Somebody picked that house and came up and shot several times on the backside of it. It looks like there was a target.”

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"Luckily, most of the women and children were inside," he said.

Some of the survivors initially listed in critical condition were now in stable condition, according to police.

Three people — all Asian men between the ages of 25 and 38 — died on the scene, Reid said during an overnight press conference. A fourth man died later at hospital while in surgery. All those shot were between 25 and 40 years old.

Fresno police Deputy Chief Andrew Hall said that two unidentified suspects walked into the backyard through an unlocked side gate and immediately began firing into the crowd of about 16 people who were outside.

"This party was described as being very peaceful, very quiet," Hall said. "It was not described as being out of control in any way. It was just a family event."

Though Hall could not confirm a motive, he said that he does believe the incident was a targeted event. Authorities are investigating whether the shooting was tied to a disturbance from earlier in the week involving two guests.

#BREAKING MASSIVE police response in a neighborhood by Peach/Pine in Fresno. Streets clogged with cars/ambulances...a lot of people being put on stretchers. Waiting to learn more. pic.twitter.com/HUT03Cdryp — Dennis Valera (@dennisreports) November 18, 2019

Police described the neighborhood as a quiet working-class area that is predominantly made up of Hispanic and Southeast Asian families, specifically those in the Hmong ethnic group. Two of the victims in the shooting were well known in the Hmong community, authorities said.

Hall said part of the investigation would include the formation of an Asian gang task force but could not confirm any of the victims had any gang ties.

“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," Hall said.

Authorities are looking to get ahead of the violence before the Hmong New Year celebration in December, which draws thousands of Southeast Asians to the community, Hall said.

Police were canvassing the neighborhood, searching for surveillance video from nearby homes that might help them discover the motives for the shooting and who was behind it, Reid added.

The shooting in southeast Fresno followed another one earlier Sunday when a man in his 20s was shot to death at a home, according to The Fresno Bee. Police have said they were investigating whether there was a link between the two incidents.

The violence also comes on the heels of a shooting at Saugus High School, north of Los Angeles, in which a 16-year-old boy opened fire on his fellow students, killing two and wounding three, before shooting himself in the head. The gunman died the next day.

CORRECTION (Nov. 18, 2019 7:10 a.m.): An earlier version of this story misspelled the name of Fresno's deputy police chief. He is Michael Reid not Reed.