Markets regulator SEBI on Tuesday directed National Stock Exchange to pay more than ₹ 625 crore in the case of misuse of its co-location facility.

SEBI has been probing alleged lapses in high-frequency trading offered through NSE’s co-location facility.

Besides, the bourse’s two former chief executive officers -- Ravi Narain and Chitra Ramkrishna -- have been asked to disgorge 25 per cent of respective salaries drawn during a certain period.

They have also been prohibited from “associating with a listed company or a Market Infrastructure Institution or any other market intermediary for a period of five years,” SEBI said in a 104-page order.

According to the order, the exchange has also been prohibited from accessing the securities market directly or indirectly for six months.

The bourse “shall disgorge an amount of ₹ 624.89 crore... along with interest calculated at the rate of 12 per cent per annum from April 1, 2014 onwards to the Investor Protection and Education Fund (IPEF) created by SEBI,” the order said.