SEOUL -North Korea tested four strategic cruise missiles on Friday as part of a drill to demonstrate its ability to conduct a nuclear counterattack against hostile forces, according to state media.

The exercise on Thursday involved an apparently operational strategic cruise missile unit of the Korean People's Army, which fired four "Hwasal-2" missiles into the sea off the east coast of the Korean Peninsula, according to state news agency KCNA.

Other units conducted firepower training at hardened sites without using live ammunition, according to the report.

The four strategic cruise missiles arrived at their destination after traveling "2,000 km (1,243 miles) in elliptical and eight-shaped flight orbits for 10,208 seconds to 10,224 seconds," according to the report.

The drill demonstrated "the DPRK nuclear combat force's war posture, bolstering in every way its lethal nuclear counterattack capability against hostile forces," according to KCNA, which uses the initials of North Korea's official name, the Democratic People's Republic of Korea.

South Korea and Japan, which are usually the first to detect and publicly report such launches, did not make any announcements.

The South Korean defense ministry said the launch was monitored, but there were "differences" between what it and the US detected and the North's statement, without going into further detail.

The launch occurred as officials from the United States and South Korea participated in a tabletop, or simulated, exercise focused on the possibility of North Korea using a nuclear weapon.

In a separate statement, Pyongyang's foreign ministry chastised Washington and its allies for convening a UN Security Council meeting in response to its recent missile tests.

North Korea has accused the United Nations of being "unfair" to its military activities while remaining silent on joint military exercises between the United States and South Korea.

North Korea will consider "strong countermeasures" if the UN continues to serve as a "U.S. tool to pressure" Pyongyang, said Kwon Jong Gun, the ministry's director general for US affairs.

"If, under the influence of the United States and its followers, the Security Council becomes a venue that judges justice for injustice and legal for illegal, it will only result in negative results that exacerbate military tension," Kwon said in a statement carried by KCNA.

Despite sanctions imposed by United Nations Security Council resolutions that prohibit the nuclear-armed country's missile activities, North Korea has advanced in developing and mass-producing new missiles.

Many launches, including an intercontinental ballistic missile (ICBM) on Saturday, have been reported as drills to improve the capabilities of troops operating the weapons by state media.

"These demonstrations may be considered missile exercises rather than developmental testing," the Center for International and Strategic Studies, based in the United States, said in a report this week.

South Korean lawmakers said on Wednesday that North Korea could test-fire ICBMs on a lower, longer trajectory and conduct its seventh nuclear test this year to perfect its weapons capabilities, citing intelligence officials.