Two people were found with their throats slit Tuesday morning in South Philadelphia -- Philadelphia Police were investigating the killings.
The bodies of 78-year-old Eugene C. Zappacosta and Janet Burgess, 50, were found wrapped in blankets in an apartment on the 1300 block of Dickinson Street, according to police.
It appeared they were stabbed and their throats were slit, cops said.
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Police believe Burgess was sexually assaulted but say they won't know for sure until an autopsy is complete.
Two dogs were also found stabbed to death inside the apartment.
Whoever committed the killings apparently tried to cover their tracks by turning on a gas stove to start a fire in the third-floor apartment, cops said.
Witnesses say they called police to report a gas smell in the neighborhood.
The property's landlord was investigating the gas smell when he discovered the bodies. Zappacosta was found in a bathroom while Burgess was discovered in the living room, cops said.
There were no signs of forced entry, officials said.
There was however evidence of drug use in the apartment, sources told NBC10.
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