Officials investigating the deaths of 6 people found dead in a Milwaukee home reveal they have 4 people in custody.

Sunday afternoon, officers conducted a welfare check at a Milwaukee home, and found 5 men and 1 woman fatally shot.

The medical examiner formally identified the victims Monday night as Charles Hardy, 42, Caleb Jordan, 23, Javoni Liddell, 31, Donta “Michael” Williams, 44, Michelle Williams, 49, and Donald Smith, 43.

Reports from the medical examiner’s office show three of the six victims, Michelle and Donta Williams, along with Donald Smith, lived in the same home.

Investigators say that this was a targeted attack and three of the six victims were expected to testify at a murder trial.

Milwaukee Police Chief Jeffrey Norman said the individuals in custody are not considered suspects at this time but persons of interest. He adds that they are looking for multiple suspects.

On Monday, he said investigators discovered a woman called 911 about 12 hours before the victims were found and claimed to be the victim of a shooting.

The 911 caller said there were also several other victims and gave two locations which were not the home where six were discovered, Norman said.

The chief said officers responded to the two locations the caller provided, but they did not find any victims.

He also said investigators tracked down the 911 caller and she was not injured.

Her connection to the killings remains under investigation.

Anyone with any information is asked to please call Milwaukee Police at (414) 935-7360 or to remain anonymous, contact Crime Stoppers at (414) 224-TIPS or P3 Tips App.