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FORT WORTH (CBSDFW.COM) – There is new information about the victims of a violent accident in Fort Worth involving an 18-wheeler. Five people were killed early Sunday after stopping on Interstate-30. The Good Samaritans were apparently trying to help a driver that had crashed.

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Monday the Tarrant County Medical Examiner identified a third victim in the crash as 18-year-old Clarissa Alexandra Banda-Castillo, of San Antonio.

The difficulty in identifying two remaining victims speaks to just how violent a scene greeted first-responders over the weekend. In fact, sources say the sex of two of the victims could not be readily determined. That could explain why more than 36 hours later, the medical examiner has still not released their identities.

In addition to the five killed, a dozen more were injured after stopping at the scene of the crash. According to police, the Good Samaritans were standing in the roadway when an 18-wheeler slammed into the group. Investigators say the driver did try to brake but could not stop the truck in time.

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Veroniza Gonzalez, 42, was killed, as was 43-year-old Mary Hernandez.

Family members are still in shock. Lisa Martinez’ sister was killed in the accident. “She was a beautiful person, had a caring heart [and] loved to help people… that’s what she did everyday. She went and helped people who needed help, that couldn’t get out of their homes to go to the hospital or the doctor, she went and took them and drove them wherever they needed to go all the time, or she’d stay overnight to make sure that they were okay through the night. A very loving person.”

Neighbors say an Aledo couple was also involved in the crash. The husband was killed and the wife is in critical condition at a local hospital, but neither police nor the medial examiner have officially confirmed those victims or released their names.

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