The two dead men had also been tied up with duct tape, police said. Their bodies were about 50 feet apart in water 5 to 10 feet deep near the river bank, and both were weighted down.
The surviving man said he was abducted off the street in West Philadelphia by a group of men with a van. He told police the other victims were in the back of the van and appeared to be already dead.
The man, 20, said he was secured with duct tape and a bag was put over his head. He was stabbed and robbed.
The dead men appeared to have been stabbed, police said.