TEMPLE, Texas — A Waco family is mourning the death of a mother after she was hit and killed when a rock was thrown from a Temple overpass.

33-year-old Keila Flores was killed Saturday when a rock crashed through the windshield of a vehicle her boyfriend was driving as she sat in the passenger’s seat, police said.

Chris Rodriguez said he and Flores were driving back from Austin along I-35, with Flores' three children in the back seat, when a rock larger than a football flew through the windshield from the railroad overpass in Temple.

RELATED: Woman dies after rock from overpass crashes through windshield, police say

Rodriguez said he pulled the car over as soon as he could and started CPR on Flores with the help of a good Samaritan who also pulled over. Rodriguez said his girlfriend made it to the hospital alive, but passed away Sunday morning.

Rodriguez said the grieving process is just starting and he has questions:

"I want to know the why. What was the reason for it? Was it just enjoyment? What do you get out of hurting an innocent person for no reason?" he said.

Police said they’ve gotten other reports of people throwing objects into traffic, but this is the first time it's led to a person's death.

There are no suspects in connection to the incident, but police said the person responsible could face a murder charge.

Temple police are asking anyone with information about the case to come forward or call them at (254) 298-5500.

Rodriguez wants people to remember, "If you throw things into traffic you could kill someone. There is a good chance you will go to prison."

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