New Delhi, May 7 -- The National Stock Exchange and BSE have barred access to their respective websites from all overseas locations to safeguard against cyber attacks effective Tuesday, two people said.

The development came a day before the Indian defence forces launched 'Operation Sindoor', raining a barrage of missiles on terror camps in mainland Pakistan and Pakistan-occupied Jammu and Kashmir a fortnight after terrorists killed more than two dozen tourists in Kashmir's Pahalgam area.

"BSE being a critical market infrastructure institution (MII) proactively and continuously monitors risks at domestic and international level for potential cyber threats," a spokesperson for the stock exchange told Mint.

"Based on such monitoring of cy...