One man was killed and another was being treated for life-threatening injuries, following an alleged carjacking that led to a collision.

An off-duty California Highway Patrol officer who was in Las Vegas over the weekend for his bachelor party was killed during a high-speed carjacking on the Strip, authorities said Monday.

Jesus Manuel Magdaleno Jr., 33, of Visalia was loading luggage Sunday into the back of his 2009 Nissan pickup with his brother-in-law Felix Brandon Cruz outside the Flamingo hotel when a thief jumped into the truck and got behind the wheel.

The carjacker then sped off, as Magdaleno jumped into the bed of the truck to join Cruz, 31.

Magdaleno was thrown from the truck after the driver struck another vehicle a mile away. The CHP officer died at the scene. Cruz, who also was ejected, remained in critical condition Monday, authorities said.

"Jess was a stand-up guy," said Officer Scott Harris, a public affairs officer for the CHP in Visalia. He said Magdaleno, an eight-year veteran of the force, had worked patrol on the graveyard shift and also was a safety-training instructor for officers.

"He was getting married in September," Harris said of Magdaleno.

Police have arrested a suspect, James Montgomery, 29, also from California, who has been charged with murder, robbery, grand larceny, automobile kidnapping and inflicting substantial bodily harm, said Larry Hadfield, a spokesman for Las Vegas Metropolitan Police.

Montgomery told detectives on the scene that he does not remember taking the truck and the last thing he recalls was walking around the Flamingo hotel, police said.

Las Vegas police say the fatal carjacking demonstrates how visitors to the resort city need to remain aware, even during a task as simple as loading luggage outside a hotel.

"I think everyone should try to be aware of their surroundings, wherever they are," Hadfield told the Los Angeles Times. "Take the extra precaution of turning off the ignition and taking the keys when you are not around your car. That precaution could have been a factor in this incident. It could have changed what happened."

The incident occurred about 11 a.m. in the valet area of the hotel. The two California men were loading the truck -- one was handing luggage up to a second in the bed -- when the carjacker jumped behind the wheel.

In a mile-long escapade, the thief ran four red lights on Flamingo Road across Interstate 15. At the last light, at West Flamingo Road and Valley View, the truck struck the other vehicle, causing Magdaleno and Cruz to be ejected.

Television reports Monday showed the crumpled white truck outside the Rio All-Suites Hotel & Casino, nearly a mile from the site of the theft.

The carjacker was also being treated for unknown injuries. Three people in the other vehicle were treated and released, police said.

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