Despite positive US jobs data, S&P 500 index extended losses on Thursday in line with analyst expectations as investors kept holding a pause after sharp rally in first three months. US benchmark fell 0.72% or 10.11 points and closed at 1,392.78 with nine of ten sectors posting substantial losses. Watson Pharmaceuticals rallied 3.8% on reports it is in talks to purchase European peer Actavis for around USD 7 billion. The shares of Discover Financial Services added 2.7%, after the company reported a 36% increase in its 1st-quarter net income.