CAMDEN, N.J. (CBSNewYork/AP) — The family of three 11-year-old girls involved in a fatal school bus crash in southern New Jersey last week is offering thanks to all those who have supported them.

Triplet Isabelle Tezsla was killed and sisters Natalie and Sophie were severely injured. Their father is New Jersey State Trooper, Sgt. Anthony Tezsla.

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Natalie was upgraded from critical to stable condition last Friday. Sophie remains in critical condition, along with classmate Jonathan Zdybel. Seventeen other students on the bus were also hurt.

Chesterfield Township police say a school bus carrying 25 Chesterfield Elementary students was on its way to the school last Thursday when a dump truck hit the driver’s side rear of the bus at an intersection. The impact then sent the bus crashing into a pole.

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The Tezsla family said in a statement Tuesday that the outpouring of love and support has touched them profoundly. They also thanked rescue workers, doctors and nurses for their efforts.

The National Transportation Safety Board is investigating the crash between the bus and the truck, but so far, no charges have been filed against either driver.

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