Amid growing tension of possible threat of North Korea attacking the U.S., the Pentagon has launched a rocket from the Santa Barbara County coast on Tuesday that hit and destroyed a mock warhead fired into space from across the Pacific Ocean, reports said citing U.S. officials.

It was a moment of great triumph for the Pentagon’s Missile Defense Agency. Vice Adm. Jim Syring, director of the Pentagon agency in charge of developing the missile defense system, referred to Tuesday's historic test result as "an incredible accomplishment" and a critical milestone for a program, which was being hampered by setbacks over several years, the Washington Post reported.

ReadPentagon Awards Lockheed Martin $427M For Anti-Armor Missiles

The test occurred just days after North Korea launched its ninth missile this year. U.S. officials said that this test had been planned for years. The ground-based interceptor was launched from Vandenberg Air Force Base in California shortly after 3:30 p.m. EDT. Just one hour after the launch, the Pentagon confirmed that it had successfully collided with an ICBM-class target over the Pacific Ocean, according to ABC News.

This test came amid the U.S.' efforts of ramping up its other missile defense programs, including the deployment of the THAAD missile defense system to South Korea, which is designed to counter short, medium and intermediate range missile threats. The U.S. military announced earlier this month that the THAAD missile defense system had become operational, CNN reported.

Although Tuesday's test of Ground-based Midcourse Defense (GMD) system was successful, it was not designed with the expectation of a significant North Korean missile threat. The military wants to prepare itself to be able to shoot down a small number of ICBMs from North Korea targeting the U.S, the Post reported.

Laura Grego, a senior scientist at the Union of Concerned Scientists, which had criticized the missile defense program, called the interceptor an “advanced prototype," which means it is not fully matured technologically even if it has been deployed and theoretically available for combat since 2004. However, she said that Tuesday's test could demonstrate the Pentagon is on the right track with its latest technical fixes.

After the announcement of intercept, Rep. Adam Smith of Washington state, the ranking Democrat on the House Armed Services Committee, said in a statement, “It’s good that the Missile Defense Agency is finally doing” a test against an ICBM target “after an investment of more than $40 billion since 2002.”

"This is an important milestone in the program, but much work remains to be done to ensure we have a reliable and effective system," he said.

The GMD system will protect the U.S. from a limited nuclear strike by a non-superpower such as North Korea. The system has 36 operational rocket interceptors — four at Vandenberg and 32 at Fort Greely, Alaska, according to the Missile Defense Agency spokesman. The agency plans to increase the fleet to 44 by 2017 end by adding interceptors at Fort Greely, the Los Angeles Times reported.