Richard and Rita Zajko were landlords renting out several homes in Aston.
CHESTER HEIGHTS, Pennsylvania (WPVI) -- Police believe the murder of a couple in Delaware County, Pennsylvania is not considered to be a random act of violence.
Pennsylvania State Police responded to a home on the unit block of Highland Drive in Chester Heights just before 5:15 p.m. on Monday, Jan. 2 for a welfare check.
Arriving troopers found Richard and Rita Zajko dead inside their home.
The Delaware County Medica Examiner has ruled the manner of death as a homicide.
On Tuesday, Pennsylvania State Police released an update on their investigation.
"The Criminal Investigation Unit has executed numerous search warrants, conducted dozens of interviews, and have obtained new evidence regarding this homicide. Based off this information it is believed at this time not to be a random act of violence," state police said.
Richard, 72, and Rita, 69, were landlords renting out several homes in Aston.
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The homicide remains under investigation.
Anyone with information can call Pennsylvania State Police at 484-840-1000 or anonymously contact the Pennsylvania Crime Stoppers at 1-800-4PA-TIPS.