A truck plant explosion in a small southeastern Minnesota town injured six people Wednesday but many more employees could have been hurt, authorities said. Many employees at McNeilus Truck and Manufacturing Inc. in Dodge Center who would have been in the area of the paint shop explosion were off-site at a training exercise when the blast happened around 10:30 a.m., Dodge County Sheriff Scott Rose said. Six people were injured, Rose said. Two were flown by medical helicopter to a St. Paul hospital and two were taken by ambulance to a Rochester hospital. Their conditions were not immediately available. Another two were being treated at the scene for minor medical issues, the sheriff said. McNeilus is part of Oshkosh Corp. in Wisconsin. Oshkosh Corp. spokeswoman Katie Hoxtell said five injured employees were "under medical care." She said she could not give details. Rose said it's his understanding "it was quite an explosion." All employees have been accounted for, he said. The complex closed production for the day, and investigators remained inside. Rose said the scene is safe and the road outside the complex has reopened after being closed following the explosion. The company will work with local authorities on the investigation, Hoxtell said. Minnesota Occupational Safety and Health investigators also will investigate, agency spokesman James Honerman said. The plant, on a 145-acre campus, makes cement trucks and refuse trucks and is a major employer in Dodge Center, a town of 2,700 about 70 miles southeast of Minneapolis. Employment fluctuates between 1,000 and 1,200, Mayor Bill Ketchum said. "Anytime you have something like that - big town or small town - it's a tragic thing. It could have been a lot worse than it was," Ketchum said.