ABERDEEN, Md. (WJZ) — Two siblings were fatally shot in Aberdeen early Tuesday morning in a murder-suicide.

According to the Aberdeen Police Department, 55-year-old Thomas Peterson of Aberdeen shot his sister 56-year-old Linda Ota of Hackensack, NJ before turning the gun on himself in the 300 block of Mt. Royal Ave.

Ota was transportaed to Maryland Shock Trauma, where she later died. Peterson was found dead by police.

The victims are brother and sister.

Police are still investigating the shooting, but believe the siblings were involved in a domestic-related argument before the incident

Detectives are still trying to establish a motive for the shooting.

This story was updated on April 10, 2015.