South Korean defense minister said Thursday that the Democratic People's Republic of Korea (DPRK) has moved an intermediate-range missile to its east coast for test- firing or military drill.

"It was not a KN-08 missile, but it can reach a significant distance," Kim Kwan-jin told lawmakers at a parliamentary defense committee meeting. "It cannot reach the U.S. mainland. The missile seemed to be moved for the test-firing or military drill purpose."

His comments came after Japan's Asahi newspaper said earlier that the U.S. spy satellite spotted the DPRK's freight train heading for its east coast. The train was loaded with a missile, estimated to be KN-08 that is believed to have a range of 10,000 kilometers and can strike the U.S. mainland, according to the report.

According to South Korean officials cited by Yonhap News Agency, the missile was estimated to be a 'Musudan' missile that is projected to have a range of between 3,000 and 4,000 kilometers and can target the U.S. military base in Guam.

The officials said the DPRK will highly likely fire it off around the middle of April, when Pyongyang celebrates the birthday of Kil Il-sung, the founder of the DPRK and the late grandfather of Kim Jung-un.

The U.S. Defense Department said Wednesday that it will deploy a Terminal High Altitude Area Defense System (THAAD), or a land- based ballistic missile system, to Guam as a precaution to strengthen the regional defense posture against the DPRK's ballistic missile threats.

Tensions have been running high in the Korean Peninsula since the DPRK conducted its third nuclear test on Feb. 12 in protest against the joint military drills between Seoul and Washington.

The DPRK declared that it entered "a state of war" with South Korea, saying that the state of neither peace nor war has ended in the Korean Peninsula. It has also threatened to launch a preemptive nuclear strike for self-defense, mentioning military bases in the U.S. territory of Guam and the U.S. state of Hawaii as possible targets.