South Korean stocks were down Monday in the wake of sluggish manufacturing indices and concerns caused by the reversal of U.S. government bond yields.

The benchmark Korea Composite Stock Price Index(KOSPI) lost 42-point-09 points, or one-point-92 percent. It ended the day at two-thousand-144-point-86.

It's the largest one-day decline for the index since October 23rd last year.

The tech-heavy KOSDAQ also fell, losing 16-point-76 points, or two-point-25 percent, to close at 727-point-21.

On the foreign exchange, the local currency weakened four-point-one won against the dollar, ending the session at one-thousand-134-point-two won.