The victims are the sisters of Iowa State Representative Mary Wolfe.
Authorities reportedly questioned the male for hours on Wednesday and executed a search warrant at his home.
The man was released around 3 a.m. Thursday and no charges have been filed against him, according to the station.
“…There’s a lot of work that needs to be done,” said Allegheny County District Attorney Stephen Zappala. “It was necessary today to detain an individual to facilitate part of the investigation.”
The man who was questioned reportedly has several prior arrests for burglary and robbery.
The bodies of Susan Wolfe, 44, and Sarah Wolfe, 38, were found February 7 in the basement of the home they shared in the East Liberty neighborhood of Pittsburgh. Both women died of single gunshot wounds to the head.
Sarah Wolfe was a psychiatrist for Western Psychiatric Institute and Clinic. Susan Wolfe was a teacher's aide at Hillel Academy in Pittsburgh's Squirrel Hill neighborhood. Their sister, Mary Wolfe, is an Iowa Democratic state representative who lives in Clinton, Iowa.