NEW YORK (MarketWatch) - U.S. stocks had one of the strongest opens this year, as big jumps in the S&P 500 and Dow Jones Industrial Average send them into record territory. Buying of stocks was spurred by news that the Bank of Japan increased its stimulus package in order to reignite its economy. The Dow Jones Industrial Average hit an intraday record after jumping 154 points, or 0.9%, to 17,350.93. The S&P 500 opened above its previous record close, adding 19 points, or 0.9%, to 2,013.14. The Nasdaq Composite jumped 65 points, or 1.4%, to 4,631.06.