Two men have now been charged with the murder of a grandmother shot dead in her home in April.

The woman killed in Sydney’s southwest was potentially the unintended victim of an escalating “beef”, NSW Police said.

One man, who was allegedly involved in the drive-by shooting of 65-year-old Kim Duncan on Dickens Rd at Ambarvale, remains on the run.

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WATCH THE VIDEO ABOVE: Murder charges over shooting in Sydney’s southwest.

Jesse Evans, 34, and Manase Fakahau, 19, were refused bail at Bankstown Local Court on Wednesday after being charged with murder.

The pair of accused killers are due to face court again in September.

Police say Duncan was not the intended target of the shooting.

“It was a person that resided at the house she was shot at,” Detective Superintendent Grant Healey told reporters.

Three men were seen getting out of a sedan and firing shots at the Dickens Rd home, where Duncan was fatally hit, in CCTV footage released in May.

A 21-year-old woman and a 34-year-old man inside the home were not injured.

The home’s occupants, who authorities believed had lived there for six to eight weeks, were known to police.

“We believe the people involved had a grudge, an argument, or a beef with somebody that lived at that location,” Healey said.

The two men charged were also known to police, and the alleged drive-by shooting was a “cowardly response” to the circumstances causing the grudge.

“While they’re trying to give somebody a lesson, they’ve (allegedly) killed some little kid’s grandma,” Healey said.

Healey said Duncan’s family were glad to hear news of the arrests but still angry about her death.