In a dramatic show of force, the United States launched a Minuteman 3 nuclear missile from an underground bunker in California on Thursday, with the huge rocket streaking into the sky and hitting its test target in the Pacific Ocean off Hawaii 2,500 miles away, Newsmax reported.

It was the second time this month that the U.S. launched its only remaining type of intercontinental ballistic missile (ICBM) out over the Pacific.

The test launches were made amid growing concern about North Korea's efforts to produce nuclear weapons capable of reaching the U.S. mainland.

The Minuteman 3 missile, carrying a payload of test instruments rather than a nuclear warhead, arced toward its test range in the waters of the Kwajalein Island chain southwest of Honolulu, Hawaii.

Officials said the U.S. is testing its ICBMs to confirm the reliability of the Cold War-era missile and all its parts. The Minuteman 3 was first deployed in 1970 but has long surpassed its original 10-year lifespan. It is so old that vital parts are no longer in production, the officials said.

The U.S. Air Force reportedly operates 450 Minuteman missiles – 150 at each of three missile fields in Wyoming, Montana and North Dakota. A few times a year, one missile is pulled from its silo and trucked to Vandenberg, minus its nuclear warhead, for a test launch, according to Newsmax.

Aside from confirming the Minuteman missile's technical soundness, the test launches serve to sharpening the message to potential U.S. aggressors that the U.S. is ready to unleash its full nuclear might against them if they try to attack the U.S homeland.

Explaining the importance of the test launches, Deputy Defense Secretary Robert Work said they are "a signal to anyone who has nuclear weapons that we are prepared to use nuclear weapons in defense of our country, if necessary."

Air Force officials say the test launches also boost the morale of the launch crews as they participate in an actual launch. Otherwise, all they do on 24-hour shifts all year-round in underground missile command posts is to hope that the call to combat never comes, Newsmax said.