India's auto sector is facing a downturn, which industry executives say is the worst suffered by the industry, triggering massive job cuts and factory shutdowns. Initial estimates suggest that automakers, parts manufacturers and dealers have laid off about 350,000 workers since April, a senior industry source told Reuters earlier this week. New Delhi-based Jamna Auto's customers include General Motors Co, Toyota Motor Corp and Tata Motors Ltd, India's largest automaker by revenue, according to the company's website.