UPDATE: Arlington County police have ruled this a homicide-suicide. The victim Xiomara Aracely Benitez and the subject Juan Carlos Mox were married with two children. The cause of death has not been determined.
Arlington police are investigating the deaths of two people found Tuesday afternoon inside an apartment building as a possible murder-suicide.
The bodies of the two -- who police say were each 30 -- were found at the Park Shirlington Apartments in the 4500 block of 31st St. S. They were involved in an intimate relationship with each other, police said.
A relative called police after discovering the bodies shortly before 3 p.m.
This is the first homicde in the county since March 2010.
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