SEOUL — North Korea appears to be readying another test of a powerful, new medium-range missile, following a series of failures for a ballistic weapons program that aspires to threaten the US mainland, multiple reports said Tuesday.

Japanese and South Korean media quoted official sources as saying North Korea looked to have deployed a so-called Musudan missile near its east coast.

The North has made four failed attempts this year to test fly the Musudan, which has an estimated range of anywhere between 2,500 and 4,000 kilometers (1,550 to 2,500 miles).

The lower range covers the whole of South Korea and Japan, while the upper range would include US military bases on Guam.

"We have detected signs that the North has deployed what appears to be a Musudan missile," South Korea's Yonhap news agency quoted an unidentified government official as saying.

Japan's Kyodo News agency and public broadcaster NHK both cited unidentified sources as saying preparations for a missile launch might be underway.

The Ministry of National Defense in Seoul declined to confirm the reports but said it was "closely monitoring the situation."

UN resolutions ban North Korea from any use of ballistic missile technology, although it regularly fires short-range missiles into the sea off its east coast.

In Tokyo, chief government spokesman Yoshihide Suga partially confirmed a Kyodo report that Japan's military had been ordered to intercept any missile or falling parts that might threaten Japanese territory.

"We ordered the Self-Defense Forces to take necessary steps ... to protect our people's lives and property," Suga said.

First unveiled as an indigenous missile at a military parade in Pyongyang in October 2010, the Musudan has never been successfully flight-tested.

Three failures in April were seen as an embarrassment for the Pyongyang leadership, coming ahead of a rare ruling party congress that was meant to celebrate the country's achievements.

The latest attempt in May was also deemed to have failed.