Some 49,000 General Motors walked off the job at midnight on Sunday

United Auto Workers union began national strike after contract talks hit impasse

Came after manufacturer's 4-year contract with workers expired without an agreement on a replacement 

UAW officials said the two sides remained far apart in the contract negotiations

It has been described as the first major stoppage at GM in more than a decade 

Analysts say work stoppage could cost GM $50million in daily losses before taxes and interest

Workers are demanding pay raises as well as increased production in plants that the company has made idle

Management is trying to bring costs under control in uncertain economic environment made worse by tariffs and rising prices of raw materials