* STX Group shares tumble, banks also drop
* Autos hit by profit-taking after recent gains
SEOUL, June 5 Seoul shares slid to their lowest close in almost four weeks on Wednesday, as concerns that the U.S. central bank might consider scaling back its stimulus programme prompted selling in growth-sensitive auto and technology stocks.
STX Group shares tumbled following media reports that shipping affiliate STX Pan Ocean will soon enter court receivership, with STX Pan Ocean becoming the biggest percentage loser on the KOSPI.
The Korea Composite Stock Price Index ended down 1.5 percent at 1,959.19 points, moving further away from the key 2,000-point level and marking its lowest close since May 13. South Korean financial markets will be closed on Thursday for a public holiday.
"The market was a bit alarmed by growing speculation the U.S. Federal Reserve may slow its stimulus programme," said Y.S. Rhoo, a market analyst at Hyundai Securities.
"There are questions about the prices of stocks and bonds ... whether they are a bit inflated," he said.
The U.S. Federal Reserve is poised to evaluate and potentially make changes to its massive stimulus, a top Fed official who is critical of the Fed's bond-buying programme said on Tuesday.
STX Pan Ocean tumbled 14.9 percent before share trading was suspended. A representative for STX Corp, STX Pan Ocean's largest shareholder, said STX Pan Ocean's future direction has yet to be decided and declined to give further details.
STX Corp dropped 14.8 percent and STX Engine slid 13.8 percent.
Banks fell on worries about their exposure to STX Group, a shipping-to-shipbuilding conglomerate, with Woori Finance Holdings and Hana Financial Group both losing 4.2 percent.
Automaker dropped on profit-taking after recent gains. Hyundai Motor declined 2.1 percent after rising more than 4 percent during a five-session winning streak. Kia Motors lost 2.3 percent.
Among techs, LG Electronics and SK Hynix both shed 3.4 percent.
Korea Electric Power Corp fell 1.9 percent after South Korean regulators said on Wednesday that they have identified two more nuclear power plants that used parts with forged test certificates.
The KOSPI 200 benchmark of core stocks fell 1.6 percent, while the junior KOSDAQ edged 2.2 percent lower.
Move on day -1.5 percent
12-month high 2,042.48 3 January 2013
12-month low 1,758.99 25 July 2012
Change on yr -1.9 percent
All-time high 2,231.47 27 April 2011
All-time low 93.10 6 January 1981 (Reporting by Jungyoun Park; Editing by Chris Gallagher)