The National Stock Exchange on Thursday said the unavailability of an ‘online risk management system’ led to the shutdown of trading on Wednesday. It is also awaiting a detailed root cause analysis from its telecom service providers and vendors, the exchange said.

Market regulator Sebi on Thursday affirmed it will take all necessary measures to ensure the underlying causes, including “institutional deficiencies”, are addressed.

The regulator said the decision to stop trading in its entirety was taken by the NSE and Sebi was informed of it only 10 minutes before trading screens froze on Wednesday.

The Association of National Exchanges Members of India said in a letter to Sebi that the glitch caused huge monetary losses to members and investors.

Zerodha faces flak

Brokerage Zerodha is facing a backlash from traders who saw their equity positions abruptly closed during a glitch on Wednesday. Hundreds of traders, who bought stocks via Zerodha, voiced their concern on Twitter, with many posting pictures showing portfolio losses due to trades squared off by the broker. Many signed an online petition for action.

“My six months salary has gone...I’ll sue you,” said Twitter user Aashish Kumar.