Investigators said a string of physical evidence at two crime scenes led them to the man suspected of killing four people Thursday in Laurel, Nebraska.Court documents reveal how Nebraska law enforcement compiled evidence against the 42-year-old Jason Jones, who was found by a state patrol SWAT team badly burned in his home across the street from one of the murder scenes.Around 3:11 a.m., Laurel Fire and EMS arrived at the first crime scene and located a woman "lying inside the back door of the residence in a pool of blood," according to court documents.The woman, identified as 53-year-old Michele Ebeling, was pronounced dead on the scene.According to court documents, Ebeling appeared to have suffered two gunshot wounds, one to the chest and one to the head.Burn marks were observed on the floor, walls and furniture at the first crime scene, indicating a fire had occurred, according to court documents. First responders also observed the smell of smoke and the smell of gasoline from inside the house.According to court documents, law enforcement also saw a red fuel container inside the front door of the residence and a "discolored trail on the floor," indicating an accelerant was used.After obtaining a search warrant, officers located a black backpack in the kitchen of the first residence, according to court documents. Several receipts were inside the backpack, including one dated Aug. 3 at 4:41 p.m., to a Cubby's Gas Station in Laurel. The credit card used for the purchase was in Jason Jones' name. There was also a receipt to Fleet Farm in Sioux City for the purchase of a 6-gallon auto shutoff gas can, along with a fuel tank and camping backpack. A third receipt was to Rath's Mini Mart in Laurel, dated Aug. 3 at 7:49 p.m.According to court documents, law enforcement found security camera video at Rath's Mini Mart that shows Jones pumping gas into two cans just before 8 p.m. on Wednesday.At the second crime scene, first responders found smoke and soot damage consistent with a fire, according to court documents.Law enforcement found three deceased parties, all with gunshot wounds, inside the residence.The three victims at the second residence were identified as 86-year-old Gene Twiford, 85-year-old Janet Twiford and 55-year-old Dana Twiford.Further investigation of the scene showed a pry bar was used to gain access to the rear door of the residence, which investigators found on the ground near the rear door, according to court documents. A magazine to a firearm was also found in this area, and law enforcement found a firearm and a Molotov cocktail inside the residence, according to court documents.The firearm found in the residence was identified as a black Ruger 57, which records showed was purchased by Jones in 2021, according to court documents.When Jones was taken into custody, law enforcement said he had severe burns. Nebraska State Police said he was airlifted to a Lincoln hospital and is in serious condition as of Friday morning.According to court documents, Jones was arrested on four counts of first-degree murder, two counts of first-degree arson and four counts of use of a firearm to commit a felony.