(CNN) A night of excess at a Pittsburgh apartment ended with three people dead, four people hospitalized and a police department warning how quickly drugs can kill.

Authorities responded to a report of an unconscious man in an apartment complex elevator around 2 a.m. Sunday. The man was pronounced dead at the scene, Pittsburgh Director of Public Safety Wendell Hissrich said.

Shortly later, paramedics responded to another man a few blocks away, outside, who was "somewhat conscious" and had symptoms similar to those of the first man. He was taken to a nearby hospital, Hissrich said.

Police traced both men back to an apartment on the city's south side. There, they found five other people who also apparently overdosed.

Police investigate the scene of an apparent overdose that left several people dead.

Hissrich said he believed the victims were men between about 30 and 50 years old.

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