Five people are dead in South Carolina after a former soldier went to his ex-wife’s home and shot a man and three children before turning the gun on himself on Tuesday, March 21, authorities said.

The former military man, Charles Slacks Jr., entered the woman’s home in Sumter, South Carolina, at around 10 pm on Tuesday, using a key he still had before they broke up, according to Sumter Police Chief Russell F. Roark.

Slacks found his ex-wife’s coworker in the backyard and fatally shot him before he went upstairs to where the three kids were sleeping, with his ex following closely behind.

According to the police chief, her phone was upstairs. Slacks pointed the gun at her, and she ran to the backyard to get a phone from her coworker to call for help. The woman did not find his cell phone, and it was not long before she heard shots ring out.

The ex-soldier had just shot dead all three kids and turned the gun on himself on top of the stairs.

The children, two boys, and a girl were identified as six-year-old Aason Holliday Slacks, five-year-old Aayden Holliday Slacks, and 11-year-old Ava Holliday.

Slacks was Ava’s stepdad and the biological father of the two younger boys.

Police Chief Roark said it was hard for him to make sense of the situation and Slack’s actions of killing three innocent children while they slept peacefully in their beds.

The man Slacks shot was a military member also, and according to the police, he and Slack’s ex-wife were not in a romantic relationship and were just coworkers.

Slacks worked as a tracked vehicle mechanic from 1999 and retired in 2007. He had since become a civilian worker at the US Army Central. The man he killed also worked at US Army Central.

Authorities have not publicly identified the man who was killed pending notification of his death to his next of kin.

The town of Sumter has a strong military presence in the nearby Shaw Air Force Base, where the US Army Central moved in 2011.