CHELSEA — On Saturday night, Autumn L. Harris took sleep and pain medication but still only got two hours of rest, she later told police. The next day, prosecutors say, the 42-year-old pipefitter from Boston drank a beer and vaped a cannabis-type oil.
Shortly before 5 p.m., Harris veered off the road and allegedly crashed her SUV into five pedestrians in Revere, killing a 5-year-old girl and leaving her 2-month-old sister with life-threatening injuries, prosecutors said Monday.
Details of the crash emerged at Harris’s arraignment in Chelsea District Court, where she pleaded not guilty to motor vehicle homicide and negligent operation of a motor vehicle. Harris, who cried during the hearing, was ordered held on $10,000 cash bail.
Assistant Suffolk District Attorney Masai King said Adrianna Mejia-Rivera, 5, was pronounced dead at the scene, and her infant sister was rushed to Massachusetts General Hospital, where she remained in critical condition in the intensive care unit Monday.
A third child and two women were hospitalized for less serious injuries, as was a 30-year-old woman riding with Harris, prosecutors said.
The women and three children were walking on a sidewalk along the median strip of Route 145.
“There are no words to describe our sorrow for this innocent child and her family,” said John Pappas, the Suffolk district attorney. “We will follow the evidence wherever it leads and we will do our level best to speak on their behalf in the wake of this devastating tragedy.”
King said Harris told investigators she took the pain medication Flexeril and the sleep aid Melatonin on Saturday night but still managed to sleep for only two hours before working a full day Sunday as a pipefitter.
Police found a beer can in her vehicle after the crash, and she allegedly told authorities that she had consumed one beer earlier Sunday afternoon, prosecutors said.
In addition, Harris indicated that “she had vaped CBD oil in the vehicle and that she might have nodded off at the wheel,” prosecutors said.
“Harris was unable to take a breath test. Investigators obtained a search warrant for a blood sample and her cellphone to help determine whether she was impaired or distracted at the time of the collision,” they said in a statement.
CBD, or cannabidiol, is a minimally psychoactive compound that can be derived from marijuana or hemp.
It is widely available at health stores and even gas station counters.
Her lawyer, Jeff Miller, said in court that his client had been prescribed pain medication and that the crash appears to have been an accident.
Outside the courthouse, Harris’s mother, Maureen, cried as she told reporters that “a lot of hearts are broken, especially hers. And I feel so bad for those children.”
She said she’s praying “that there’s a solution as to what happened, because she loves kids.”
Her daughter called her after the crash and told her through tears, “I don’t know, all of a sudden it just happened,” Harris said. Her daughter “doesn’t know if the medication she’s on . . . might have contributed. I don’t know, we’ll find out,” she said.
She said her daughter is “obviously in shame” over the crash.
“I just want to hold her,” Harris said. “She’s probably suicidal at this point. Wouldn’t you be? It’s terrible.”
Autumn Harris had previous interactions with police. She was charged with drunken driving in 2011, prosecutors said. That case was continued without a finding. In 2011 and 2014, she refused to take chemical breath tests, according to the Registry of Motor Vehicles.
Relatives of Mejia-Rivera did not attend the arraignment and could not be reached for comment.
George J. Rotondo, a Revere city councilor, said Adrianna “was Revere’s daughter, and we all mourn for her.”
“Our hearts bleed for the family,” he said.
City Councilor Patrick Keefe said the fatal crash was “truly tragic.”
“Our prayers are with the Mejia-Rivera family,” he said. “We also pray for the well-being of the youngest victim still in intensive care.”
City Councilor Joanne McKenna said the intersection where the crash occurred is dangerous for pedestrians.
The council has been pushing for better street lighting and lane markings there for more than a year.
“That’s a bad intersection,” McKenna said. “It’s not lit up well.”
At the Revere elementary school that Adrianna attended, grief counselors were on hand, Mayor Brian M. Arrigo said.
“We are overcome with sorrow by this unthinkable loss,’’ Arrigo said in a statement. “On behalf of the entire City of Revere, I express our deepest and most heartfelt condolences to the family, knowing that no words can begin to ease their pain and sadness.”
Harris is due back in court Jan. 10.
Danny McDonald of the Globe staff contributed to this report. Travis Andersen can be reached at email@example.com. Follow him on Twitter @TAGlobe. John R. Ellement can be reached at firstname.lastname@example.org. Follow him on Twitter @JREbosglobe.