The victims, 67-year-old Marilyn Beasley and 60-year-old Marcy Strager, died of smoke inhalation, according to police.
The two women who survived have been identified as Elaine Demona, 69, and Dorothy Gerano, 54.
Police are also blaming a space heater for sparking the blaze, and the heater has been removed according to Alliance Against Homelessness of Bergen County, which operates the home.
The fire broke out inside the house on Berkshire Road Tuesday just after midnight.
Here is video of the fire:
A Fair Lawn police officer fell off the roof while trying to help and was injured, but is expected to be OK.
"I saw smoke coming out of the second floor," said a neighbor, Steve Maiman. "I knew there were elderly people there, a group home, so I knew it could be a bad situation."
Police officers went in looking for the four women. Officer John Rovetto found one of them.
"I knocked on the door real quick and pulled on the door handle to see if it was actually open. It was and she was standing right in the living room," said Rovetto. "I pulled her out and said we need to leave."
Officials say the fire began in a second floor bedroom. Two of the women upstairs died in the fire. Another climbed out of a window and onto the roof. At the same time officers were still searching as best they could.
"We looked upstairs and they were fully engulfed," said Rovetto. "If any of us tried to go up there it wouldn't have worked out well for anyone. We checked the downstairs and made sure nobody else was downstairs. Then we came to the garage, opened the garage and found the bed frame."
That bed frame was used as a rescue ladder by the officers, as firefighters were arriving.