A woman is comforted after the bodies of two children were found stabbed to death in their father’s apartment Aug. 4 in Houston. (Elizabeth Conley/Houston Chronicle/AP)

The calls kept coming. It was last Saturday, and Sabine Ntongo was reportedly working at her Houston-area hair braiding business. Hours earlier, she had dropped her children off with her husband, Jean Pierre Ndossoka. Now he was repeatedly ringing Ntongo throughout her workday.

Their relationship was in its end stages. Married for six years, Ndossoka and Ntongo had emigrated together from Congo to the United States, where they both became naturalized citizens. But as family members would later allege, multiple media outlets including CBS affiliate WLKY reported, Ndossoka was verbally abusive. His wife left with the children — but custody was a new tension between the couple. Ndossoka wanted to see his children — Anna-Belle, 1, and Marcel, 8 — every day.

When Ntongo finally answered one of Ndossoka’s calls last Saturday around 3:30 p.m., what the estranged husband said suddenly switched a visitation dispute into a nightmare.

According to court documents obtained by USA Today, Ndossoka said on the phone with Ntongo that he had killed their children. He said he “left a present for her” at his apartment. He said the house key was under the doormat.

Ntongo called 911 and rushed to Ndossoka’s home, an apartment in a two-story tan building set behind a black metal fence in southwest Houston. In the unit’s back bedroom, she found the children on the bed. Their throats had both been cut. A bloody knife lay on the floor. ABC 13 reported a hand-scribbled note, written in French, also was left with the bodies. The message told Ntongo she would have to “carry the burden of our souls, me and my two children.”

“I am dying with my two children,” Ndossoka, 62, allegedly wrote before signing off.

But Ndossoka was gone. Police quickly issued an alert for the suspect, who they said had fled in his black Nissan Titan truck. As crime scene investigators arrived at the apartment, sealing the scene with yellow caution tape, friends and family began pooling in the complex’s parking lot as light rain fell.

“The kids were stabbed and that’s what we do know,” Houston Police Assistant Chief Wendy Baimbridge told reporters at the scene.

Patrice Nsuary, Ntongo’s cousin, told WLKY he had recently counseled the couple about their deteriorating relationship.

“I came down here to talk to both of them about the marriage. In Africa, we talk to both the man and wife,” Nsuary said. “I spoke to him yesterday.”

Nsuary also said he had seen Ndossoka and his son at the grocery store the day before the killings. “He seemed fine.”

“We don’t understand,” another distraught family member told the station. “It’s just unbelievable. We don’t know why.”

Police located Ndossoka’s truck in the Houston suburb of Pasadena around 1 a.m. on Sunday, the Houston Chronicle reported. He was inside, suffering from an apparent self-inflicted gunshot wound to the head. According to the Chronicle, he was taken to the hospital with nonlife-threatening injuries. Police believe he had tried but failed to kill himself.

When investigators initially interviewed the father from his hospital bed, he claimed at first he didn’t remember what had happened in the apartment. Pressed by investigators, Ndossoka finally admitted he had done “something bad,” according to court records.

When police asked Ndossoka what had happened, he motioned toward his neck.

The father then recounted his children’s final words before he wielded the knife, court records said. Anna-Belle just cried. Marcel pleaded with his father. “Daddy, I’m sorry,” the boy said.

Court records indicate Ndossoka has been charged with two capital murder charges. He does not have a lawyer listed.

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