It was around 10:00 a.m. when the SPCA responded to a stable in the 3200 block of North 11th Street.
There, investigators say, they found one dead horse and three still alive. The living horses were being rescued by Tuesday afternoon, the SPCA said.
At least some of the living horses were "in bad physical shape," the SPCA said.
In a news release issued Tuesday afternoon, the SPCA said it had been investigating the stable operation for several weeks, saying the owner illegally rented out stall space to a number of people.
The SPCA described the stables as a "series of ramshackle structures."
"Because there are no ordinances prohibiting the ownership of horses in the city, this is common problem we face," said George Bengal, director of humane law enforcement at The Pennsylvania SPCA said in a statement. "Unfortunately, these animals often end up suffering from cruelty and neglect because they are not kept in conditions conducive to the need to their needs."
The SPCA went on to say that, in the past year, they have rescued two emaciated horses and two deceased horses from the same lot and ordered the owner to cease operations and remove all animals.
Still, in defiance of the order, horses remained on the premises and additional horses were brought there within the last week, the SPCA said.
The Pennsylvania SPCA anticipates charging both the owner of the property and the owner of the dead horse with animal cruelty charges pending the outcome of the investigation.