At 12.30pm, the FBM KLCI was down 5.46 points to 1,578.78, sliding under the 1,580 support as investor sentiment in global equities turned sour.
After a promising early start, Asian markets retreated amid fears that positive Chinese economic data would lead to policy tightening.
Regional indices erased earlier gains, led by Japan's Nikkei dropping 1.1% while China's composite index slid 0.3%.
Back home, bank counters led the decline with Maybank losing seven sen to RM8.27, Public Bank slipping two sen to RM4.20, Hong Leong Bank shedding six sen to RM18.60 and CIMB falling six sen to RM4.29.
Sime Darby Plantation shaved 13 sen to RM4.54 while Kuala Lumpur Kepong dropped 24 sen to RM22.62.
Amid the broader decline, tech stocks continued to rise, led by MPI rising 84 sen to RM40.54, Greatech adding 33 sen to RM6, D&O Green Technology climbing 17 sen to RM4.81 and KESM gaining 14 sen to RM12.94.
Name plates manufacturer Volcano, which debuted on the ACE Market today, was up 14.5 sen to 49.5 sen, off its day's high of 70.5 sen.
Meanwhile, profit-taking in Berjaya Corp pressured its share price four sen lower to 40 sen on the back of 144.7 million shares traded.
Other top traded counters were Dagang Nexchange down 5.5 sen to 80.5 sen and Ta Win up 2.5 sen to 45 sen.