The collision took place in Middlesex County in Cromwell on Route 9 around 5:20 p.m. on Monday, Sept. 11.
According to State Police, Devoni Miller, age 24, of Cromwell, was traveling southbound in a 2016 Hyundai Sonata when she allegedly hit the back of a 2010 Kia Forte driven by Hartford County resident Cheryl Robbins, age 59, of Rocky Hill.
The impact caused the Hyundai to cross the center median and strike the metal guardrail on the right shoulder, state police said.
After the crash, Miller, along with her daughter, Deroyal Miller, who was a passenger, left the scene on foot and ended up on the banks of the Connecticut River, state police said.
Police said Robbins, the driver of the first vehicle, drove herself to Middlesex Hospital for suspected minor injuries.
Later, the 2-year-old was found dead among the rocks of the river. The mother, who received minor injuries during the crash, was also found, police said. Both were transported to Middlesex Hospital.
"The death of the child is deemed suspicious and remains under investigation," state police said.
Investigators seek witnesses to the accident and/or anyone who may have dashcam footage. Anyone who may have witnessed the accident, or seen anything suspicious on the river is asked to contact Det. James Bria at james.bria@ct.gov.
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