An explosion Thursday evening in Fitchburg destroyed a single-family home, displaced neighbors and sent one man to the hospital. The 57-year-old homeowner was conscious when he was taken to a hospital with significant injuries, authorities said. He was in critical condition Thursday night, Fitchburg Fire Chief Joe Pulvermacher said. The home at 5573 Cheryl Drive near South Fish Hatchery Road was a total loss. Three houses in the neighborhood also sustained major structural damage and may need to be demolished, and 23 other structures had minor to moderate damage, authorities said. Debris from the explosion spread across South Fish Hatchery Road, which was closed from McKee to Lacy roads. Pulvermacher said the debris scattered more than half a mile from the explosion. Authorities said that in an effort to preserve as much evidence as possible, as well as ensure the safety of the public, South Fish Hatchery Rd will be closed through the night, with one lane in each direction of re-opening at 6 a.m. Friday. East Cheryl Parkway and Cheryl Drive (from Research Park Drive to the east to Florann Drive to the west) will continue to be closed to traffic until the investigation has been completed. The cause of the explosion was not known, but Pulvermacher said gas was still leaking at the scene for hours after the explosion. Madison Gas & Electric was on the scene and brought the gas leak under control, he said, and gas and electricity were shut off to four houses.