Secretary of Defense Ashton Carter. (AP photo)

Defense Secretary Ashton Carter announced a “Hack the Pentagon” contest in April, which he called “an unprecedented effort to test our digital security in the first ever federal government bug bounty.”

“At the U.S. Department of Defense (DOD), we fight off sophisticated cyber attacks everyday. So it might surprise you to know we are about to roll out the welcome mat to hackers,” Carter said in a statement Wednesday.

Hackers will be required to register with the Pentagon and submit to a background check before participating in a “controlled, limited duration program that will allow them to identify vulnerabilities on a predetermined asset,” Carter said, adding that “this bug bounty will not compromise any of the department’s critical, mission-facing systems.”

“Under the pilot program, we will allow qualified participants to identify vulnerabilities on the Department’s public web pages,” he added, noting that the contest is “modeled after similar competitions conducted by some of the nation’s biggest companies – Microsoft, Google, and Facebook - to improve the security and delivery of networks, products, and digital services.”

Carter’s announcement did not specify whether there would be a financial reward for the "white hat" hackers who expose vulnerabilities in the Pentagon’s computer systems.

Last August, NBC News reported that the Pentagon’s Joint Staff email system had to be taken offline after it was targeted in “a sophisticated cyberattack” by alleged Russian hackers.