* Emkay placed 59 erroneous orders - exchange
* Nifty index dropped more than 900 points, or 15 percent
* Trading halted for 15 minutes
* Nifty index resumed - down 0.75 pct
(Updates with NSE statement on Emkay, details)
MUMBAI, Oct 5 (Reuters) - India's largest stock exchange was brought to a brief halt on Friday after a local financial firm placed more than five dozen erroneous orders worth more than $125 million, triggering a sharp fall on the Nifty stock index .
The National Stock Exchange said a single dealer terminal at Emkay Global Financial Services placed 59 erroneous orders for an institutional client, resulting in trades worth over 6.5 billion rupees. The trades triggered a sudden drop of more than 900 points on the 50-share Nifty index to a session low of 4,888.20 points - 15.5 percent below Thursday's close.
After resuming, the index last traded down 0.7 percent at 0709 GMT.
"These non-algo market orders have been entered for an erroneous quantity which resulted in executing trades at multiple price points across the entire order book, thereby causing the circuit filter to be triggered," the NSE said in a statement.
An exchange source declined to comment on whether those misplaced trades would be reversed, or what would happen to any other trades placed at the time of the trading halt.
Officials at Emkay, a financial services firm founded 17 years ago, did not respond to multiple requests for comment.
Trading on the NSE, whose $731 billion market value exceeds that of Bombay's Sensex (BSE) index , was halted for around 15 minutes during morning trading. NSE futures and options markets traded as normal and the BSE was uninterrupted.
Some financial stocks, which make up more than a fifth of the exchange's value, fell sharply before trading was halted, including State Bank of India and mortgage lender HDFC .
In April, a sudden drop in Nifty futures sparked speculation of an erroneous trade, but the exchange said no errors had been spotted on its trading systems.
($1 = 51.8650 Indian rupees)
(Reporting by Abhishek Vishnoi and Manoj Dharra; Writing by Rafael Nam; Editing by Ian Geoghegan)
Keywords: INDIA NSE/TRADING