Authorities checking on a car stranded in a field Saturday morning found two people killed by a powerful storm that raked the state a day earlier with more than a dozen tornadoes, AP reported. The Friday storm destroyed several buildings and left at least four people injured in Stafford County, including one hospitalized in serious condition at a Wichita hospital, according to a statement by Sharon Watson, a spokeswoman for the Kansas Adjutant General's Department. The National Weather Service said at least 17 twisters touched down across the state. Authorities found a man and woman from Colorado dead in a car in a field 13 miles (21 kilometers) east of Pratt, about 75 miles (120 kilometers) west of Wichita, Watson said. It was not clear how the car got in the field. In a statement about the deaths, the Pratt County Sheriff's Office did not give details about how the two were killed, and declined to elaborate when called. Severe weather continued on Saturday in northwestern Oklahoma, where a tornado touched down in a rural area west of Hennessey. Television footage showed a twister severely damaging barns. No injuries were reported. In Colorado, hundreds of residents were allowed to return to their homes in the farming town of Windsor, which was ravaged by a large tornado on Thursday. Parts of the town had been cordoned off because of natural gas leaks. Officials met with residents to advise them of the dangers still in the area from exposed electrical wires, severed gas lines, nails, broken boards and other debris still littering the area. About 100 people have died in U.S. twisters so far this year, the worst toll in a decade, according to the weather service, and the danger has not passed yet. Tornado season typically peaks in the spring and early summer, then again in the late fall.