Seven were killed in New York state after a trailer disconnected from a truck and slammed into a minivan carrying two families, on Route 13 in the town of Truxton, south of Syracuse.
Four of the dead were children under the age of 10, reported 18WETM news, while the other three dead were adults in their early twenties. One man survived.
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Authorities aren't sure why the trailer came loose, reported CNN, and weather isn't thought to be a factor. No one on board the tractor-trailer was harmed.
“They tried to miss it, but he ran out of time,” said Truxton first assistant fire chief Ken Stone to the Associated Press. “All of a sudden, a trailer is coming at you and there’s no truck on it."
“Tore it right apart,” he said of the van. “It was humbling, especially young kids. It tears you up.”
The victim's names have yet to be released by the Cortland County Sheriff's Office.