Tokyo stocks fell Friday on cautions ahead of the U.S. jobs data with the key Nikkei index down 0.51 percent.

The 225-issue Nikkei Stock Average slipped 44.89 points from Thursday at 8,831.93, bringing an end to a three-day winning streak. The broader Topix index contracted 1.76 point, or 0.23 percent, to end at 760.69.

The sectors leading the decline included the pulp and paper, glass and ceramics, and iron and steel sectors. The electric machinery, oil and coal products, fishery and forestry sectors were among the winners.

Tokyo stocks trading returned to normal operations Friday after the bourse was affected by a glitch in its market data distribution system on Thursday, which led to suspended trading of 241 issues in the morning.

The opening for Friday was mixed. At 9:15 a.m., the 225-issue Nikkei Stock Average lost 18.53 points, or 0.21 percent, from Thursday to 8,858.29, while the broader Topix index expanded 0.78 point, or 0.10 percent, to 763.23.

Selling pressure prevailed throughout the day as investors were watching closely the monthly U.S. employment data. The crucial monthly jobs data always set the tone for the market in a week or two.

Investors also watched for signals from Federal Reserve Chairman Ben Bernanke, who testified before U.S. lawmakers on Thursday. Bernanke described the pace of the U.S. economic recovery as "frustratingly slow," although he said the Fed anticipated higher levels of growth in the coming year than in 2011.

The turnover was about 1,261 billion yen (about 16.55 billion U. S. dollars).