A fender-bender led to life-threatening injuries for two drivers on Interstate 494.

The drivers were standing near their damaged vehicles on the shoulder when another motorist lost control of his SUV and struck them, authorities said Sunday.

The chain-reaction crash occurred shortly before 6 a.m. Saturday along Interstate 494 near the Pilot Knob Road exit on the Mendota Heights-Eagan border, the State Patrol reported.

Hospitalized with life-threatening injuries were Derek D. Nelson, 47, of Lakeland, and Paul G. Holler, 59, of Eagan, the patrol said. Holler was in critical condition Sunday, while Nelson's condition was serious, according to hospital spokespeople.

Many road surfaces throughout the metro area were glazed over from the combination of snow and extremely cold weather.

Any crash scene along the freeway "is always dangerous due to the speed of passing vehicles, [and] in inclement weather there is an even greater risk due to reduced traction on the roadway surface," State Patrol Lt. Tiffani Nielson said Sunday. "If the vehicle is drivable, exit the freeway to a safer location like a city street or parking it."

While it is tempting to quickly get out of a vehicle at the spot of a crash and take photos of the damage, Nielson continued, "Never exit the vehicles … until a trooper arrives."

According to the patrol:

Nelson's SUV hit Holler's minivan as both drivers were heading west on I-494, sending both vehicles into spinouts.

The drivers moved their vehicles onto the shoulder and got out. A Lexus SUV driven by 19-year-old Torrey D. Nixon of St. Paul hit the minivan, sending it into the two men standing outside their vehicles.

Nelson was taken to Hennepin County Medical Center in Minneapolis, while Holler was transported to Regions Hospital in St. Paul.

Nixon suffered noncritical injuries and was taken to Regions. A passenger with Nelson, 19-year-old Madeline M. Nelson, was slightly hurt and not hospitalized.