Blue-chip stocks extended their losses today as the renewed threat of higher interest rates convinced investors that the strong corporate earnings of the second quarter might be in jeopardy.

After dropping as much as 100 points in early trading, the Dow Jones industrial average closed 58.26 points lower, at 10,910.96. For the week, the Dow lost 298.88 points, or 2.7 percent.

Broader stock indicators were mixed, as the Nasdaq composite index, which had fallen steeply earlier this week, managed a last-minute gain of 7.96, closing at 2692.40. For the week, the Nasdaq lost 6.1 percent of its value.

Banks and brokerages led the Dow lower today, as Thursday's remarks by Federal Reserve Chairman Alan Greenspan continued to worry Wall Street.

Greenspan told Congress that while 1999 has been an exceptional year for the U.S. economy, the central bank would "act promptly and forcefully" by raising interest rates at the first hint of inflation pressures.

Financial services stocks were the hardest hit today. J.P. Morgan, down 2 3/4 at 133-9/16, was the weakest component of the Dow.

Other big brokerages such as Merrill Lynch, which was down 2-5/16 at 71-11/16, also tumbled. Those businesses are generally the first to suffer from rate increases, because clients postpone borrowing in view of the higher costs.

The threat of higher rates also sent bond prices plummeting for a second straight session, pushing the yield on the 30-year Treasury bond up to 6.02 percent from 5.96 percent late Thursday. Traders consider bond yields above 6 percent a threat to stocks, because at that level, bonds present an attractive investment alternative. The 30-year bond's price fell $7.19 per $1,000 invested.

Debate over Greenspan's message deflected some attention from the latest companies to report strong earnings.

"After Greenspan's speech, many believe that the Fed may be more aggressive than expected," said Alan Ackerman, senior vice president at Fahnestock & Co. "The fear of higher interest rates is overshadowing the strong earnings we are seeing."

Among the positive earnings news today was a report from Sun Microsystems, which said its fourth-quarter profit grew a better-than-expected 30 percent. Sun's stock rose 3-3/16, to 70 3/8. Computer seller Gateway rose 10 1/8, to 73, after it reported a 47 percent increase in second-quarter earnings.

Most other high-technology leaders were lower, also stumbling under the weight of Greenspan's comments.

America Online and Microsoft both fell, despite the fact that both posted strong earnings this week. AOL retreated 2-9/16, to 107-15/16; and Microsoft slipped 13/16, to 90 1/4.

Declining issues outnumbered advancers by nearly 2 to 1 on the New York Stock Exchange. Volume totaled 635.7 million shares, down from 785.5 million on Thursday.

The Standard & Poor's 500-stock index fell 4.03, to 1356.94; the NYSE composite index fell 2.91, to 638.87; the American Stock Exchange composite index fell 3.48, to 796.29; and the Russell 2000 index of smaller companies lost 3.11, to 448.38.