US stocks fell modestly in heavy trading as investors secured some gains from Wednesday's rally, which put the Dow Jones industrial average above 8,000 for the first time. The Dow fell by about 19 points to 8,019 despite a big gain by Merck, which reported better-than-expected earnings.

The blue-chip barometer briefly dipped under the 8,000mark during the last hour of trading, but bounced back as bargain hunters moved in.

Declining issues outnumbered advancers by a 9-to8 margin on the New York Stock Exchange, with 1,296 up, 1,586 down and 555 unchanged.

NYSE volume totalled 629.06 million shares as of 4pm, Vs. 646.03 million in the previous session. The Standard and Poor's 500-stock list fell 5.01 to 931.58, and the NYSE composite index fell 2.28 to 482.96. The Nasdaq composite index fell 11.65 to 1,568.98.

- (AP)