The C&S Transport company employees showing up to work early this morning were shocked to learn their employer, Tami Mathison, had presumably perished in a fire at her family home late Thursday night. Yakima County Fire District 5 firemen, assisted by Sunnyside firemen, arrived on the scene just after 11 p.m. to find the two-story house on Northwest Crescent Avenue totally engulfed in flame. According to Yakima County Deputy Fire Marshal Ron Rutherford, the firemen were unable to get inside the house to rescue Mrs. Mathison. She is still unaccounted for and presumed to have died in the fire, according to Yakima County Fire District 5 Capt. Joel Byam. According to Byam, the firemen learned, while still on their way to the fire, that the house was still occupied by an occupant and that this occupant was at the rear of the structure, standing in an upstairs window. On the arrival of the first fire truck, firemen found that the two-and-half story residence was over 50 percent involved, as well as the near-by trees and a vehicle that was ablaze. The first units in attempted to place a ladder to the rear of the structure, but due to intense heat and flames they were unable get close to the structure. As firemen continued to arrive on the scene the second story collapsed onto the first floor, blocking further access, making it unsafe for the firefighters to enter the building. Rutherford, who was on site this morning investigating the fire scene, said the firemen were further hampered in their efforts to control the house fire because of C&S Transport's fleet of cars blocking some of the access to the house. According to reports, the fire quickly spread from the second story to the first floor and to the garage, destroying everything in its path. The attached garage, where much of C&S Transport's automotive materials were believed to be stored, was burned to the ground, as was the back yard pergola. Also destroyed in the blaze was a car, and one van was damaged. According to neighbors, Mrs. Mathison had apparently gone back into the house, believing one of her five children was stuck inside. Family members told the firemen that they could see her standing in a second story window and were yelling for her to jump. "They think she was afraid to jump. She never came out," said Katie Martin, who has lived next door to the Mathison family for the past nine years. Her husband, Marty Mathison, suffered burns to his arm, but the couple's five children escaped the fire and are currently staying with family members. Early this morning the last of the fire crews left the scene and turned over the investigation to the Yakima County Fire Marshal's Office. Arrangements were being made to bring heavy equipment to the scene to assist in the investigation and recover the body of the missing woman. Mathison's 10 employees were unable to provide transportation to the company's many clients as the keys to the company fleet also were destroyed in the fire. "It's all such a shock," said longtime employee Steve Anderson. It is not known at this time in which part of the house the fire started or how the blaze was ignited.