Firefighters spent hours in freezing temperatures battling a fire at a commercial building in Linden. The blaze broke out around 12:30 a.m. Tuesday and eventually went to three alarms. It was still burning more than 6 hours later. Video from NewsCopter 7 showed heavy smoke and flames shooting through the roof of the facility before dawn. The one-story building near the intersection of East Elizabeth and North Park avenues houses World Class Kitchens, a food preparation company. Fire officials say the blaze started in a kitchen area. Eyewitness News is told the building was occupied when the fire started. One worker was treated for smoke inhalation and taken to an area hospital. Traffic on Routes 1&9 about a block away was moving normally for the morning rush hour.