General Motors

(GM) - Get Report

became the latest in a string of large companies to warn about less-than-robust demand Monday, sparking selling pressure among auto shares and taking a bite out of the broader market, too.

Compared with May, "demand has slackened" in June for GM cars, according to Bob Lutz, the vice chairman for product development. His comments were carried in wire reports from an industry group meeting in Montreux, Switzerland. "The planned surge in demand never quite materialized," Lutz reportedly said.

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Shortly after the comments were reported, GM shares were down $1.02, or 2.1%, to $46.63. Shares of

Ford

(F) - Get Report

fell 28 cents, or 1.8%, to $15.57, while

Toyota

(TM) - Get Report

dipped 24 cents, or 1.5%, to $16.32. Meanwhile, the

Dow Jones Industrial Average

, which had been sitting on a 50-point gain, faded and was recently up 14 points at 10,384.

Shares of

DaimlerChryser

(DCX)

bucked the trend, rising 30 cents, or 0.7%, to $46.84.

Lutz's warning is worrisome confirmation for investors that remained unconvinced about the auto industry's health even after Ford raised profit guidance earlier this month. While the automaker said, on June 16, that full-year earnings would be well above its old guidance of 30 cents to 35 cents a share, most of the upside was coming from Ford's lending arm.