DeKalb County detectives spent a frantic weekend trying to piece together details of a murderous crime spree that left a witness to a killing dead, as well as what they believe was a retaliatory home invasion where a 9-month-old baby was shot to death and three women wounded.

Police were seeking two teens who apparently set off the tragic set of events a week earlier, when they allegedly killed a man at a party. And there was also a drive-by shooting that left two men dead and three other people wounded, which police have since determined were not related.

In all, four people were dead and six were wounded in the string of events.

“It’s complicated,” said DeKalb Police Chief Cedric Alexander as he explained the violent timeline. Later, he addressed the brutality and brazenness of the crimes. “It’s insane. It’s insane. I’m sure it’s terrifying to the residents of that neighborhood.”

Police are looking to arrest Cutrez Johnson, 16, also known as “Lil Red,” and Oslushla Smith, 19, who is also known as “Budda” or “Boo,” in connection with the May 3 shooting of Michael Phillips, 29, at a party in south DeKalb. Another man, Kemontay Cullins, 18, was arrested early Sunday in connection with the May 3 killing. Police said Johnson and Smith are also wanted in connection with the fatal shooting of Alexis Malone, 19, who witnessed the May 3 killing.

Police said Johnson and Smith either lived in the home where the baby was killed or “had relationships” with the residents. The home on To Lani Farm Road is in a neighborhood off Redan Road in south DeKalb.

Police believe the gunmen Saturday were either looking for Johnson and Smith or simply deadset on brutal retribution when they came to four bedroom, cream-colored home that once was a daycare and was purchased three years ago in foreclosure for $18,000.

The women inside were awake when either three or four gunmen, their faces covered with bandannas, kicked in the back door after 10:30 p.m., Alexander said. “The three women took the baby and rushed upstairs, tried to lock themselves inside the bathroom, the gunman kicked the door in and commenced firing on all of them,” he said.

The baby boy died at Children’s at Egleston hospital. The three women, ages 36, 23 and 21 were taken to Grady Hospital. Alexander said all should survive their wounds. Police did not identify the women or the baby but said they believe the 21-year-old was the boy’s mother.

A neighbor of the home said that the teen known as Lil Red was breaking into homes in the neighborhood. She said she brought police to his house months ago to report a television stolen from her home. Another neighbor said, “whenever he comes around, there’s trouble.” Several neighbors said a girl about 14 years old lives there and often had several friends there. The Atlanta Journal-Constitution is withholding their names to help protect them from retribution.

Alexander said Johnson (“Red”) and Smith have police records. The neighbor said “Lil Red” was locked up for several months late last year and early this year.

Police said on May 3 they were called to The Mountain Lake apartment complex on North Hairson road, where Phillips had been shot to death by a wound to the head. On Friday, the department put out a Crime Stoppers alert to help solve the crime.

A 25-year-old Mountain Lake resident told the AJC he ran out of his apartment nearby when he heard gunshots May 3. He said numerous people were in a garden apartment watching the Floyd Mayweather championship fight, drinking and socializing, spilling outside into a grassy area at the corner of the building. The man, whose name the newspaper is withholding for fear of reprisal against him, said some young uninvited guests arrived, leading to a fight, which then got worse because, he said, “everybody had guns.”

He said the gunmen had come at Phillips, the victim, from two sides and he raised his hands as if to surrender. That’s when he was shot, Smith said, adding that he is told the shooters were members of the Bloods street gang.

Police will not say if they believe the shootings are gang related.

Alexander said police got an anonymous call about 6 p.m. Saturday, saying there was a dead woman on Agape Way, a relatively quiet street that runs along I-285, not far from the later shootings. Police arrived on the scene and found the body of Alexis Malone, who they say witnessed the killing a week earlier at the party.

Police are seeking Malone’s friend, Kayla Dixon, 20, as a person of interest but not a suspect. “We’d like to talk to her as soon as possible,” Alexander said.

DeKalb County police spokeswoman Mekka Parish said the Malone’s death and the baby’s death are not related to a drive-by shooting Saturday evening that left two men dead and three other people wounded, a case they originally worried might be connected. That case happened around 7 p.m. on Shamrock Drive, south of Decatur, where a car followed another car and then occupants of the trail vehicle opened fire.

One man and two women were wounded in that attack and were taken to hospitals. No names have been released in that case.