Updated

A pickup truck's front tire that apparently had come apart was likely the cause of a weekend crash on a rural South Texas highway that claimed its 15th victim Tuesday, authorities said.

The truck packed with 23 suspected illegal immigrants crashed Sunday evening near Goliad, about 90 miles southeast of San Antonio. Eight passengers remain hospitalized. Investigators were working to identify the victims, who they said are from Mexico, Honduras and Guatemala.

"More than likely the crash was caused by front right tire separation," Texas Department of Public Safety spokesman Gerald Bryant said Tuesday.

The investigation into the crash continues, and Bryant would not say if the tire was old and worn or if the separation was a manufacturing issue. He did not name the tire brand.

Eleven people died at the scene, including two girls. Four more died later at hospitals, including a man who died Tuesday.

Bryant identified the driver as 22-year-old Ricardo Mendoza-Pineda, who died in the crash.

Mendoza-Pineda was from Mexico, Bryant said, but he could not comment on his immigration status. Bryant said interviews with survivors indicated the truck was bound for Houston.

The Mexican Consulate in San Antonio had confirmed Monday that one 22-year-old man from Tamaulipas, which borders Texas, was among the dead. Bryant said he did not know what part of Mexico Mendoza-Pineda was from.

In a statement, the Guatemalan government said at least two Guatemalans died in the accident, a 27-year-old man and a 22-year-old woman.

Crashes of vehicles overloaded with illegal immigrants moving north from the border occur periodically, often as they attempt to evade authorities.

In April, nine Mexican immigrants died near the border when the teenage driver of their van crashed after fleeing Border Patrol. There were 18 people in that minivan.

In that case, six adults face a variety of federal charges and the 15-year-old driver was charged in state court with nine counts of murder.