WASHINGTON – Loudoun County prosecutors have determined that a shooting at a Sterling Costco in May was justified.

A prosecutor’s report found the Loudoun County Sheriff’s deputies acted in self defense and in self-defense of others when 38-year-old Mhai Scott was shot and killed on May 29 inside Costco.

Authorities say Scott went at two deputies with a knife and scissors before she was fatally shot. A total of five shots were fired and Scott was hit with four.

The deputies had ordered Scott to drop the weapons but she advanced on them.

Authorities also say the Taser that had been used on Scott did not perform properly. It was supposed to last five second, but it only lasted one second.

Officials have sent the Taser back to the manufacturer to investigate what happened.

The prosecutor’s report also noted that Scott had a history of mental illness.

Scott worked for Club Demonstration Services, who provides services to Costco.

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