LOS ANGELES — Three men associated with a gang have been arrested in connection with two deadly Los Angeles shootings in a case in which all suspects and victims were from the Chicago area, police said Friday.

Investigators would not specify the motive for the shootings that killed three women and wounded four other people in January and a man in December.

“We can’t discuss the motive, but we can say that it’s associated with Chicago,” Capt. Jonathan L. Tippet, commanding officer of the Los Angeles Police Department’s Robbery-Homicide Division, said in a news conference at police headquarters.

“One thing that can be said is that the violence that occurs in Chicago today is having an effect on all of us,” Tippet said.

He said the three suspects are “involved in” and “connected to” a gang but would not go into further detail about their relationship with the group.

The arrests followed a nation-spanning investigation involving numerous law enforcement agencies, including the FBI violent crime task forces, Tippet said.

Dejean Thompkins, 28, was arrested last month in the Chicago area. Dontae Williams, 22, was arrested in April in Gary and transferred to Chicago. Daries Stanford, 28, was arrested May 10 in Manhattan. All three are awaiting extradition to Los Angeles.

Around 2:30 a.m. on Jan. 28, Iyana Hutton, 33, of Chicago, Nenah Davis, 29, of Bolingbrook, and Destiny Sims, 26, of Buckeye, Arizona, were shot to death in a car as they returned to a vacation rental house in Los Angeles’ Beverly Crest area after a night out.

The women grew up together and had gone to Los Angeles in support of a Chicago rapper, according to Tippet, who said they were not the intended targets of the attack.

Four other people were wounded, and two others escaped injury in the attack, in which more than 30 rounds were fired. Their identities are being withheld, Tippet said.

Investigators connected that shooting to the Dec. 16 killing of Julian Bynum, 30, on a North Hollywood sidewalk outside an apartment complex.

“In both of these cases, the suspects used ambush-style tactics on their unsuspecting victims,” Tippet said. “Planning and coordination was utilized.”

The slain women weren’t connected to Bynum, who Tippet said is believed to have been targeted.

Tips from the public about the getaway car used in the Beverly Crest shooting were important in the investigation, he said.

The Los Angeles County district attorney’s office filed four counts of murder and six counts of attempted murder against Thompkins. Williams and Stanford each was charged with three counts of murder and six counts of attempted murder. All three also were charged with six counts of assault with a semiautomatic firearm.

“This was a careless and senseless act that has left the victims’ families stunned and devastated,” Los Angeles County District Attorney George Gascón said. “This is another example of the widespread damage that can be done by gun violence.”

Upping the potential penalties if they are convicted, the complaint also says the crimes involved special circumstances of lying in wait and multiple killings.