Defense contractor Lockheed Martin has been linked to a cyber-attack on a firm which supplies coded security coupons to users, said a report in The New York Times.

The RSA Security division of the EMC Corporation, which develops and supports information infrastructure, supplies something called SecurID. The tokens are used by government officials and corporate employees to access computer networks from outside their offices.

But the company found in March that it had suffered a data breach which could easily compromise its security products and that the intruder had successfully stolen a trove of digital information. Military executives said the problem Lockheed is facing could appear from the data breach and can cause damage to its systems.

Most of RSA’s clients have taken extra security measures since the breach and are finding alternative solutions to deal with the problem. Some of the users are even shutting down the remote access feature, the report said.

Military officials, under the condition of anonymity, told NYT that Lockheed had spotted a trespasser trying to breach its networks last Sunday. It shut down most of its remote access and provided fresh tokens and passwords to many workers.

Lockheed specializes in spy satellites, fighter planes, and other classified equipment. The company also deals in cybersecurity for military and intelligence agencies.

A spokesperson for Lockheed said the company will not openly discuss the security threats but informed that it will take action to raise security standards.