An Atlanta school bus that caught on fire with dozens of students on board last week is one of hundreds of local school buses that officials say have been plagued with mechanical problems, though district officials say there's no apparent connection between the alleged problems and the fire.

An alleged manufacturing defect in the engines of the school buses manufactured by Illinois-based Navistar International Corporation and purchased by metro Atlanta school districts has at times left children stranded in broken-down buses, The Atlanta Journal-Constitution reported last month. The alleged defect has also left taxpayers on the hook for expensive repairs.

The school district is investigating the cause of last week’s fire, but there is no indication that it was related to the alleged engine troubles, Atlanta schools spokeswoman Kimberly Willis Green said.

The problems are in diesel engines manufactured by Illinois-based Navistar International Corporation with new technology intended to reduce pollution.

They aren't limited to the Atlanta area or to Atlanta schools. Cobb, Fulton and Gwinnett county schools are among the local districts that own buses with these engines. Some bus service companies have sued the manufacturer, and other districts are threatening legal action.

The fire last week took place on a 72-passenger bus transporting South Atlanta High School students to a track meet. The bus caught fire on I-20 West in Douglasville. The students and driver were safely evacuated and driven to the meet on a replacement bus.