TOKYO – North Korea fired two surface-to-air missiles near its border with China on Wednesday, a Japanese news agency reported, raising concerns about the reclusive regime’s potential to create instability in the region.

The Kyodo News agency offered different accounts, saying a security source in China told it the missiles were fired by mistake in the direction of China during a military drill and landed in North Korean territory.

A “Western military source,” however, said short-range missiles were test-fired from North Korea’s eastern coast toward the Sea of Japan, according to Kyodo.

At least one of the missiles had landed in the sea about 60 miles northeast of the launch site, Kyodo said, citing a Japanese defense official.

The agency said it couldn’t immediately reconcile the conflicting reports, and the exact time of their launch was not known.

North Korea would be extremely hesitant to do anything to offend China, its last major benefactor, and the type of missiles fired wouldn’t pose much of a threat to anywhere far beyond the North’s borders. Despite remaining technically at war with

South Korea, the sides have embarked on reconciliation efforts since a 2000 summit between their leaders and many South Koreans don’t view the North as a threat.

But Pyongyang shocked Tokyo and other nations when it test-fired a ballistic missile over northern Japan in 1998.

It has since test-fired short-range missiles many times, including one that was launched into the Sea of Japan in May last year. In 2003, it test-fired short-range land-to-ship missiles at least three times during heightened tensions over its nuclear weapons program.

Japan’s Defense Ministry said it couldn’t confirm the report of Wednesday’s launches. South Korean officials who monitor the North also said they didn’t have any information.

Pentagon spokesman Bryan Whitman said Wednesday that he was unaware of the North Korean missile firings.

White House spokesman Scott McClellan said administration officials were still checking into the reports. “I really don’t have more for you at this time,” he told reporters on Air Force One, en route to New Orleans.

Last year, regional governments and Washington played down the significance of the rocket launch in early May, and the real concern would come from longer-range missiles.

In Washington on Tuesday, the commander of the U.S. military in South Korea, Army Gen. B.B. Bell, said reports indicated Pyongyang was “preparing to field a new intermediate-range ballistic missile which could easily reach United States facilities in Okinawa, Guam and possibly Alaska,” according to prepared comments.

However, Bell noted there had been “very little activity” by the North Koreans in recent years on long-range ballistic missiles. Instead, he said officials have seen increasing work on short-range missiles that could be used on the Korean Peninsula.

Besides producing a large number of weapons, Bell said North Korea also “appears willing to sell to anyone.”

Analysts say North Korea is developing long-range missiles capable of reaching Alaska, Hawaii or perhaps other states on the West Coast.

Japan and the United States have started to develop a joint ballistic missile defense system, and Tokyo has said it will launch two spy satellites by March 2007 to monitor North Korea and other trouble spots.

There is no evidence North Korea has managed to load a nuclear warhead on a missile, but the isolated communist state claims to have produced nuclear weapons.

Last September, Pyongyang agreed at multilateral talks to abandon its atomic weapons program in exchange for aid and security guarantees. However, no progress has been made since then on implementing the accord.