30-year-old Robert Long, 36-year-old Nasir Moss-Robertson, and 34-year-old Keith Garner have all been arraigned on murder charges.
Philadelphia police had already charged 32-year-old Jahill Porter last month in connection with the killings.
Authorities have said they believe two stepbrothers, 31-year-old William Taylor and 28-year-old Akeem Mattox, found a stash of drugs while renovating homes.
Police say when they tried to sell the stash, the men were killed along with the two sisters, 20-year-old Tiyaniah Hopkins and 17-year-old Yaleah Hall.
(Associated Press contributed to this report)
Send a News Tip to Action News
Learn More About 6abc Apps