He was pronounced dead at the scene, Chris Togneri, a city public safety spokesman, said Sunday.
Then before dawn, authorities discovered a horrific scene at the same apartment building: two more dead men and three others with medical conditions ranging from serious to critical, Togneri said, and all with the same orange wristbands.
All the men in the incident probably overdosed on drugs, officials said.
Police are racing to piece together what happened on Saturday night, Togneri said, but have landed on a working theory that the men were at a venue together and gathered at an apartment after-party, where they took drugs together.
They have identified two venues that use orange wristbands, Togneri said, but declined to name them — saying only that they held “concerts or parties.”
“We’re trying to figure out where they were last night,” Togneri said.
Police stressed they don’t believe tainted drugs were distributed in large volume with the potential to harm others.
“We do not believe this particular incident is going to be widespread,” Pittsburgh police commander for narcotics Jason Lando said. “So we are not in a situation where we expect people to be found in an overdosed state all over the city.”
Authorities have released few details. Public Safety Director Wendell Hissrich told reporters he didn’t believe there was a party at the building, suggesting the victims had arrived there after a night out.
Hissrich speculated the two other men who were found earlier “were trying to make their way back to this location” and exhibited similar symptoms.