Amy Lafond, 52, turned herself into police on a warrant stemming from the accident in which Lilyanna Johnson, 14, and Alyssa Miner, 14, were struck in Laconia as they left their middle school, the New Hampshire Union Leader reported.
Johnson died of her injuries, and Miner was seriously injured, WMUR-TV, Manchester, said.
Lafond was charged with manslaughter, negligent homicide, second-degree assault and other charges. Police said she was arrested after a lengthy and exhaustive investigation.
County Attorney Melissa Guldbrandsen said Johnson was struck as she stood in a marked crosswalk, and that the manslaughter charge accused Lafond of driving her vehicle while distracted and at an unreasonable speed after consuming drugs.
Guldbrandsen said Lafond is also accused of possessing oxycodone and the prescription drug Gabapentin, a seizure and pain medication.
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