The Securities and Exchange Board of India (Sebi) has initiated a probe into the annulment of derivatives trades on the Bombay Stock Exchange (BSE) on the day of Muhurat trading.

The market regulator has asked for the details of the trades, and has initiated investigations into factors that led to unusually high volumes. “Trade annulment is a serious issue,” a senior Sebi official noted. “This is the first time an entire session has been cancelled in so many years. We are looking into it.”

The regulator is also likely to look into deficiencies, if any, in the process of approvals and risk management systems, followed by the exchanges for such algorithmic trades, officials said.