Woman killed mother, sister, then staged murders, police say

Woman arrested for murdering her mother and sister in 2017, police say

FAIRFAX COUNTY, VA (WJLA/CNN) - Authorities in Northern Virginia say an alleged murder-suicide of a mother and her daughter was actually a double homicide.

A family member stands accused of the killings.

For the last year, neighbors thought a murder-suicide unfolded inside a McLean, VA, home.

But investigators say they quickly learned something more sinister happened inside.

“(The) scene was staged to look one way. We know it wasn’t,” said Maj. Ed O’Carroll.

Detectives say Megan Hargan was just playing the part of a grieving loved one last July when her sister Helen and mother Pamela were found shot to death.

Fairfax County officers indeed thought they were dealing with a murder-suicide.

But detectives took a closer look, and soon realized the scene was staged and Hargan was the killer.

“We are not going to get into the specifics of what and what wasn’t staged. I will tell you that it was made to look one way. Our detectives are smart,” O’Carroll said.

So, where was Hargan around the time of the murder? Investigators believe trying to steal money from her mom.

Detectives say they interviewed Hargan twice and uncovered evidence that led them to Friday's indictment.

Hargan was arrested during a traffic stop near her West Virginia home where she will soon face a judge for the murder charges in Northern Virginia.

"I'm thankful it was a safe encounter this morning and she's in custody," O'Carroll said.

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