State Trooper Mark Piper has seen his share of car crashes while patrolling Pennsylvania's highways for 18 years, but he's never seen an accident turn out as well as this one.

"It's a miracle," he said, after Jolinda Effinger and her two children survived -- with nonlife-threatening injuries -- a 60-foot fall off Interstate 79 near Waynesburg in Greene County Thursday afternoon, after their car was bumped by another vehicle and plunged from a bridge onto the ground below.

Ms. Effinger, 43, of Greensboro, is in fair condition at Ruby Memorial Hospital in Morgantown, W.Va., after undergoing surgery.

Her two children, whose names were not released, were in good condition, according to Mr. Piper.

"God was watching out for them -- and they were all wearing seat belts," he said.

The accident occurred at around 3:15 p.m., he said, when a 1997 Jeep Grand Cherokee Laredo driven by Rhonda Lee Porterfield, 38, of Cokeburg, which was going about 65 mph in the right lane of the highway, moved into the left lane and bumped the back of Ms. Effinger's 1999 Saturn Coupe.

Ms. Effinger's car was knocked onto a jersey barrier and kept going for about 30 feet before sailing 100 feet over the edge of the bridge and down 60 feet onto Route 188 below.

Ms. Effinger's car rotated while in the air and landed on its roof, Mr. Piper said, but she was able to get out on her own. Two passers-by were able to help get the children out of the car.

"We ran up to the car, [and saw] the kids that were in it and hanging upside down still OK," Levon Reggetz, one of those who helped, told KDKA-TV. "The mother was outside of the car, so we went and got a knife and [another man] cut the seat belt down."

Up on the interstate, as police arrived to direct traffic, Ms. Porterfield had stopped her car.

"She was pretty broken up to see that car go over the bridge," said Mr. Piper, adding that she and two children riding in her car were unhurt.

An investigation into the crash is continuing, and summary charges may be filed against Ms. Porterfield. "But at this point we're still looking into whether there were mechanical problems," he said.

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