U.S. Border Patrol is investigating a deadly crash following a suspected human smuggling attempt near Brownsville, according to a Customs and Border Protection spokesperson.

The crash occurred on Sunday at around 4:30 a.m. One person was killed and four undocumented migrants were injured.

The spokesperson said Border Patrol agents at the Fort Brown Station spotted a vehicle they believed was involved in human smuggling. When agents attempted to conduct a vehicle stop, the driver fled at a high rate of speed.

The suspect vehicle ended up rolling over on FM 511. Agents immediately called for emergency medical services and began rendering aid.

One person was pronounced dead at the scene and the four undocumented migrants were taken to a local hospital for treatment, according to the spokesperson.

The Brownsville Police Department is investigating the crash.