Two men near Portage, Ind., were scouting a creek for potential fishing spots on Tuesday when they spotted a shiny object through the trees. They moved closer and saw that it was a mangled vehicle.
One of the men, Mario Garcia, said that he looked inside, pushed aside the airbag and found what he thought was a lifeless body.
But upon touch, a young man, still alive, awoke.
“He was very happy to see us,” Mr. Garcia said at a news conference. “I’ve never seen a relief like that.”
The driver, Matthew R. Reum, 27, of Mishawaka, Ind., had been trapped in the crumpled 2016 Ram truck for six days, according to the authorities.
Mr. Garcia said the man he was with, Nivardo Delatorre, immediately went up to the highway to call for help.
It took rescuers “quite a bit of time” to free Mr. Reum from the wreck, according to Sgt. Glen Fifield, a spokesman for the Indiana State Police.
Mr. Reum was airlifted to Memorial Hospital in South Bend, roughly 50 miles away, with “severe, life-threatening injuries,” the police said in a news release on Wednesday.
His condition improved from “critical” to “serious” the next day, according to a hospital spokeswoman, Heidi Prescott.
The police determined that Mr. Reum had crashed around 11 p.m. on Dec. 20 in Portage, which is about 120 miles west of Fort Wayne.
A preliminary investigation found that the pickup had been traveling westbound on I-94 when it veered off the road and barreled toward Salt Creek below, missing on its way a protective guardrail on the highway bridge.
“So he’s driving on the grass shoulder for a good length of time before he goes airborne, down into the creek, where he rolls probably several times,” Sergeant Fifield said.
The pickup ended up underneath the bridge, hiding it from drivers overhead, he said.
“Quite frankly, it’s a miracle he’s alive,” the sergeant said.
It was not immediately clear how Mr. Reum had managed to survive so long, but Sergeant Fifield noted that the unseasonably higher temperatures had worked in his favor.
The police said they had not received any reports of a crash on that stretch of highway, but that even if they had, it would have been difficult for officials to spot the wreckage from the road.
“I don’t see any way somebody could’ve seen him,” Mr. Garcia said. “It was just very fortunate that we had seen through the cracks of the woods the shining of the wreck.”
Mr. Reum told the fishermen that he had tried screaming for help to no avail.
“It was just quiet,” Mr. Garcia said Mr. Reum told him. “Just the sound of the water.”
Mr. Reum requested privacy as he recovered, the hospital spokeswoman said on Wednesday, but Mr. Reum asked for a message to be shared on his behalf.
“No matter how tough things get, there is a light at the end of the tunnel,” the message said. “Sometimes in the least expected way.”