Six people were killed and eight injured Thursday after an SUV carrying them turned over on a Texas highway. Police were in pursuit of the vehicle, which was allegedly linked to a people trafficking network.

The driver, a U.S. national, and five undocumented immigrants, were among those killed, authorities said. Leticia Zamarripa, a spokeswoman for U.S. Immigration and Customs Enforcement, said in a statement that the driver and two others in the vehicle were believed to be members of the smuggling group, the Associated Press (AP) reported.

People who were smuggled in the SUV were adults from Honduras, Guatemala and Mexico, Zamarripa reportedly said. A Mexican is also suspected to be involved in the smuggling, she added.

Police in Jackson County’s Edna city, 90 miles southwest of Houston, had tried to stop the 2003 Ford Explorer for a traffic violation, city police Chief Clinton Wooldridge said, according to the AP. However, the driver sped away resulting in a chase on Highway 59, which falls within city limits.

The vehicle rolled over several times during the chase, throwing some of its 16 passengers from the SUV, police said, adding that four of them were declared dead at the scene and two others died at local hospitals. One passenger was reportedly in a critical condition.

"We've been in contact with consulates and they are working with the medical examiner's offices to try and find these people's families," Wooldridge said, according to the AP.