A Massachusetts grand jury handed up an indictment Tuesday in connection with the mysterious death of a 15-year-old girl in Cambridge last summer.
Isaias Plaza, of Boston, was charged at Middlesex Superior Court with manslaughter and assault and battery resulting in serious injury in connection with the July 22, 2018, death of Richelle Robinson.
Robinson died of head injuries sustained when she was allegedly pushed to the ground on Cambridge Street. She was reportedly heading to an acquaintance's home when she was shoved down and hit her head.
Plaza, who hid his face in court, silently listened to the prosecutor describe the final hours of Robinson's life.
"First responders saw she had blood coming from her nose and the back of her head. She was unresponsive," Middlesex County Assistant District Attorney Nicole Allain said.
Robinson was taken to a local hospital, where she died the following afternoon.
For over a year, the case has remained a mystery, with no word of an arrest until this week's indictment was made public. Officials initially believed the attack was a robbery, but later ruled that possibility out.
Allain said Plaza and his girlfriend had some type of falling out with Robinson and her friends before he ran into her that day and with both hands shoved her to the ground. A female witnesse called 911 to report the incident.
"She saw a person who was later identified as the defendant forcefully shove her to the ground with two hands," Allain said.
After the alleged incident, Plaza took off on a bicycle, according to prosecutors.
Investigators said they were able to track Plaza down through several security cameras in Cambridge and Somerville.
Plaza, who was 18 at the time, told police he was riding in Cambridge that night but did not run into the victim. He said he left his bike out to be stolen and burned his clothes from that day just for fear of being associated with the incident. Investigators later found out he told a witness a different story.
"After leaving Cambridge, the defendant went to Boston and told a witness that while he was in Cambridge he ran into the victim on Cambridge Street and that he pushed her by accident," Allain said.
Richelle's family was in court Tuesday, wearing pins with her image on them.
According to her obituary, Richelle was a well known and active member of the community who participated in numerous local youth programs. She was a student at Cambridge Rindge and Latin.
"She was a very smart young lady who wanted to become an Emergency Medical Technician when she grew up," her obituary read. "She loved the color purple as well as doing nails and make-up. In Elementary and Middle School, Richelle became talented in singing and later moved onto dancing when she began High School at Cambridge Rindge and Latin."
"She was a very smart young lady, and very responsible," family friend DerriniQue Coleman told NBC10 Boston last year. "She was loved by many."
Plaza is being held without bail pending a dangerousness hearing Aug. 13. He is being represented by George Ohlson.