Johnston Police Chief Richard S. Tamburini said Daniel Rodriguez broke into the home of Evelyn Burgos, 40, on Sunday before fatally shooting her and her 25-year-old daughter, Vanessa Perez, and abducting Isaiah Perez.
Isaiah Perez was found unharmed Sunday night after a police officer spotted him at a public housing complex in Providence, about 10 miles from the town where his mother and sister were killed. He was temporarily placed in the care of state child welfare officials.
Rodriguez, who is either 27 or 28, was arraigned Monday on two counts of murder as well as on burglary, kidnapping and gun charges. He was arrested in Providence on Sunday and is being held without bail; police did not give an address for him. Rodriguez had no comment as he was led out of the Johnston Police Department to be taken to the state prison.
Authorities said Rodriguez is Burgos' boyfriend but not the boy's father. A nationwide Amber Alert was issued on Sunday following the boy's abduction.
Police initially said another man, Malcolm Crowell, 22, had abducted Isaiah Perez and issued a picture of him in the Amber Alert. He was arrested in Fall River, Mass., on Sunday but released after police determined he had no involvement in the kidnapping or killings. Crowell was Vanessa Perez's boyfriend and attempted to help authorities find Isaiah Perez, Tamburini said.
"He's not involved at all," Tamburini said of Crowell.
Police were still trying to determine the details of how Isaiah Perez ended up alone in Providence, Tamburini said. Police also did not offer a motive for the killings, saying the investigation is ongoing.
Two other children were in the home at the time of the shootings, Tamburini said. One is another son of Burgos and the other is Vanessa Perez's daughter. Officials said the two children were in the custody of the Department of Children, Youth and Families on Monday but would be released into the care of family members.
The victims' bodies were discovered about 5:20 a.m. Sunday at a home in suburban Johnston, a town of 30,000 residents outside Providence.
The house is in a quiet wooded neighborhood near a reservoir. The property was closed off with police tape and the Johnston police crime scene unit was there Monday morning.
Deputy Police Chief Daniel Parrillo said investigators believe the victims were killed between 4:30 a.m. and 5 a.m. Tamburini said five shots were fired.