A chain-reaction crash ­during stop-and-go traffic on an ­Indiana interstate has left a Twin Cities couple dead and their teenage ­granddaughter hospitalized with severe injuries.

The crash occurred about 12:10 p.m. Saturday on westbound Interstate 70, 35 miles east of Indianapolis, according to the Henry County Sheriff's Office.

Dead at the scene near New Castle were Sylvia K. Shaw, 66, and John L. Shaw, 66, both of New Brighton, the Sheriff's Office said.

The 13-year-old granddaughter in the SUV, Katrina Tucker of Minneapolis, was removed by emergency personnel and airlifted to a hospital in Indianapolis, where she was being treated for a broken hip, and arm and leg fractures, a hospital spokeswoman said Sunday afternoon. Her condition on Monday was upgraded from citical to serious.

"You just wouldn't believe that she was able to survive that accident," said Sheriff's Deputy Landon Dean, the first responder on the scene, calling it "a miracle [that] she is going to be OK." Everyone in the SUV had on seat belts, he added.

The Shaws' SUV was "absolutely unrecognizable," the deputy said.

The couple and their granddaughter were returning from a trip to Washington, D.C., and on their way to Indianapolis to visit relatives, Dean said.

"You could see just a little spot of bluejeans; that's how I knew someone was in the back," Dean said, recalling when he first approached the mangled vehicle. "I could hear her crying."

Dean said the back seat was "folded on top" of the girl, pushing her "down on the floorboard. I'm sure she never saw her grandparents" during the entire time she awaited being freed.

A semitrailer truck hit the Shaws' SUV from behind, pushing the smaller vehicle into the back of another big rig and then into a car, authorities said.

Dean said traffic was slowing for construction about 2 miles ahead, which was reducing the interstate to one lane.

All passengers in the other vehicles escaped without injury in the crash, which blocked westbound traffic for three hours during what Dean said was "a wonderful, sunshiny day."

The driver of the semi that hit the SUV, Richard Engstrom, 59, of Indianapolis, "didn't know traffic was stopped for some reason," Dean said. "There's a question about how long he had been driving [without a break]."

Time on the road is suspected of playing a role in a crash in New Jersey two weeks ago that critically injured actor and comedian Tracy Morgan. A National Transportation Safety Board report said the driver of the semitrailer truck that struck a van carrying Morgan was speeding and that the semi's driver had been working more than 13 consecutive hours.

Paul Walsh • 612-673-4482