A man accused of fatally shooting his ex-wife and injuring her boyfriend Saturday at the home they all shared in Tarzana was expected to be arraigned on Tuesday, Los Angeles police said.

Hrant Meguerian was arrested on suspicion of killing 51-year-old Azniv Meguerian and gunning down her boyfriend after an argument in the 4500 block of Vanalden Avenue, police said.

His bail increased from $1 million to $5 million Monday after he was taken to the Los Angeles County Jail downtown.

"It's a little unclear as to what the motive was," said Los Angeles police Detective Joel Price of West Valley Division. "But when you take a woman who has an ex-husband and a boyfriend under the same roof, the mix is volatile.

"And in this case fatal."

Police were called to the victim's residence at 7:20 p.m. following the sound of gunfire.

They found Azniv Meguerian, a native of Armenia who worked as a real estate agent, shot in the head and torso. She died later at a local hospital.

Her live-in boyfriend, Michael Carver, 49, had been shot in the back, Price said. He was hospitalized in serious but stable condition Monday.

Police arrested the ex-husband, 59-year-old Hrant Meguerian, a retiree who had moved back into the home.

The suspect had been arguing with Carver when he allegedly drew a handgun and shot both victims, police said.

dana.bartholomew@dailynews.com

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