Police said two cars were involved in a head-on collision.
"My mom was over here worried because she heard the person yelling for help and my dad rushed over there to help but the police came and told us to step away from the scene," Rodriguez said.
Police said the vehicle with the children inside, a Nissan Sentra, was heading north on Middle Street when it crossed the double yellow line and smashed into a Ford Windstar whose driver was heading south.
Firefighters pulled four people out of the Sentra, including 31-year-old Kayla Torres of Meriden, Miguel Melendez of New Britain and the two children. The children were brought to Bristol Hospital where officials said they died from their injuries.
Torres, the mother of the children, was at the wheel suffered serious injuries. Melendez, along with the driver and passenger of the Windstar were also seriously hurt.
Family said Torres is a nurse and she was heading home after working late when the crash happened.
Veronica Martinez was a second-grade student at Hanover Elementary School, and counselors were made available to help students at school.
The people in the Windstar were identified as 26-year-old Michael Luponio of Southington and 23-year-old Jonathan Oquendo-Cruz of Waterbury. Both are in stable condition.
Police said there was a third person in the Windstar and they fled on foot. They are still looking for that person.
Anyone with information is asked to contact 860-584-3033.
The family has set up a GoFundMe page to help Torres raise money for funeral costs.
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