Two separate hacker groups whose activities are already known to authorities were behind the serious breach of RSA Security earlier this year and were likely working at the behest of a government, according to new statements from the company’s president.

RSA President Tom Heiser, speaking at the RSA conference in London this week, said that the two unidentified hacker groups had not previously been known to work together and that they possessed inside information about the company’s computer naming conventions that helped their activity blend in with legitimate users on the network, according t...