The Arizona Department of Public Safety is investigating a Border Patrol vehicle chase that ended in a fatal crash outside Tucson. 

DPS says the crash happened around 11 p.m. Monday night on a frontage road off I-19, about 40 miles south of Tucson. A truck being pursued by a Border Patrol vehicle ran off the road, collided into trees and overturned. 

Passengers traveling in the truck’s cargo bed were ejected, and one person was pronounced dead on the scene. Four other passengers were transported to a Tucson hospital with life-threatening injuries. 

Bart Graves is a spokesperson with DPS. 

"We’ll interview the Border Patrol agent involved, and survivors of the crash, as soon as they’re able to respond to our questions, we’ll talk to these witnesses, maybe anyone else that was on the road," Graves said. 

A statement from Customs and Border Protection said the vehicle had failed to yield and that personnel from DPS and CBP's Office of Professional Responsibility are investigating the incident. 

Graves says information about the deceased person won’t be released until next of kin is notified.