Granville Brooks, 41, and Charmaine Goliath, 27. Picture: Jack Lestrade/ANA

Cape Town - Relatives of a Mitchells Plain woman and her mother, who were shot dead allegedly by her cop boyfriend, say he went berserk because she wanted to leave him.

The Daily Voice can also reveal that the officer, who killed himself after the double murder, lied to his girlfriend and colleagues about being divorced from his wife.

Meanwhile, the relatives blame Mitchells Plain cops for the bloodbath, saying they “killed” Charmaine Goliath, 27, and her mother, Susan April, 54, when they failed to arrest Detective Sergeant Granville Brooks after he threatened them in front of police on Wednesday night.

Instead, Brooks’ colleagues “talked him down” and let him go.

He returned to Charmaine’s Begonia Street home in Lentegeur on Thursday morning where he allegedly shot her and her sickly mother before turning his service pistol on himself.

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A shocked colleague says: “The team that was there didn’t expect that from him, they had calmed him down.”

But Charmaine’s brother-in-law, who only identified himself as Kurt, told the Daily Voice: “This should never have happened if police did their job on Wednesday evening.”

Family members and police sources reveal Charmaine’s sister had called police to their house on Wednesday night after Brooks became “violent and argumentative”.

A police source close to the investigation says Brooks, 41, who was stationed at Lentegeur Police Station, and had a “sterling record”, had threatened to “come back and kill everyone” as his colleagues escorted him out of the house.

“All I know is that there was a domestic violence dispute and that there were vans called to the house,” the source says.

“The sister called the detective commander who called the shift commander.”

“He said ‘as ek terug kom, gaan ek almal vrek maak’ (He said, when I come back, I will kill all of you ),” the source says.

Brooks had just returned from training in Oudtshoorn and had apparently lied to his girlfriend of two years about his divorce.

Neighbours in Begonia Street told cops Brooks arrived early on Thursday morning and greeted them; later they heard four or five gunshots ring out.

Cops with snipers arrived on the scene, suspecting they were dealing with a hostage situation.

When cops later rushed into the house, they discovered all three had been shot dead in the bedrooms.

Charmaine’s father was not at home, as he had gone to draw his pension.

It is believed Brooks had sent out a child, who had apparently also been at the house, to buy a chiproll.

Friends reveal Charmaine wanted to leave Brooks, “but that he didn’t take the break-up well and snapped”.

“She wanted to leave him because she found out he was still married and that he was seeing is wife.

“But it seems she was also cheating on him and he went berserk,” a close friend says.

Meanwhile, Brooks’ colleagues, friends and senior officers at his workplace say they were shocked to learn he was still married.

A close friend and colleague of Brooks’ says: “We always believed he was divorced because he claimed that he was no longer married. We heard at the debriefing on Thursday night that he never divorced, but he always said he was.”

His wife, Samantha Brooks, with whom he has two children, took to Facebook, confirming they were married, posting: “I will always love you, my husband.”