The benchmark Sensex, after recovering from the 800-odd points fall last week in the last three sessions, fell by over 300-points at 1400 hrs today, triggered by Thailand central bank's decision to impose a 10% penalty on overseas investors if they take out funds within a year of investment.S&P CNX Nifty shed 100 points, amid fears that other governments may also look into similar restrictions to insulate their markets from volatilty caused by sudden exit and entry by big foreign funds.Indian stock markets attracted about $ 9 billion funds this calendar, after record inflows of $ 10.7 billion last year. "Markets may be anticipating similar moves in India too," said an analyst, explaining the rationale of sudden fall in the stock indices.Thailand's stocks plunged by 19% following the central bank decision, which was aimed at stemming the 16% gain in the baht this year.Stocks in the other markets in the region also fell. Japan's Nikkei index declined by 1.09% while Hong Kong by 0.79%, Taiwan by 0.34%, South Korea's Kospi index shed 0.38% and Indonesia was down 3.17%.