China's military has taken over border patrol duties along the frontier with North Korea (searchin a routine administrative change, the Foreign Ministry said Monday. It gave no indication that the move was linked to North Korea's nuclear program or possible tensions over cross-border crime.

The announcement in a brief statement faxed to reporters follows Hong Kong news reports that 150,000 People's Liberation Army (search) troops have been sent to the border since mid-August to stem crime by North Korean soldiers.

The Foreign Ministry statement said it could not confirm those reports by the Sing Tao and Sunday Morning Post newspapers.

The ministry didn't say what agency previously patrolled the North Korean border, which is off-limits to foreign reporters. But such duties are believed to have been held by the People's Armed Police, a paramilitary force also controlled by the Defense Ministry.

The ministry said the change was meant to streamline administration of the border.

"It is a normal adjustment carried out after many years of preparation by the relevant parties," the statement said.

Defense analysts in South Korea (searchdiffered on whether the troop move was a Chinese attempt to pressure North Korea to make concessions in talks on its nuclear program. Beijing, the North's main ally and aid provider, has tried to convince the isolated communist government to resolve the issue by dialogue with the United States.

"Considering the relations between China and North Korea, it is difficult to imagine that China would use its military as a means to influence North Korea," said Baek Seung-joo, director of North Korea research team at the government-run Korea Institute for Defense Analysis.

Government spokesmen in the Chinese border cities of Yanji, Tumen and Hunchun said they had no information about the change in border patrol or any troop deployments.

PLA troops also patrol China's borders in the restive western regions of Tibet and Xinjiang.

The 870-mile-long border with North Korea has reportedly seen an upsurge in crossings by would-be refugees from the North and crime by North Korean soldiers.

Tens of thousands of North Koreans already are believed to live in hiding in China's northeast.

Tensions have increased since October, when North Korea admitted to the United States that it had restarted its nuclear program.

The Chinese Foreign Ministry statement said police would continue to bear responsibility for border inspection and public security work in the border region.

The statement said the PLA was also taking over border-guard duties from police along the frontier between Myanmar and southwestern China's Yunnan province.

The border, even longer than that between China and North Korea, is a key route for heroin smuggled from Myanmar for sale in China or export to other markets.

Military analysts had been puzzled by unusual Chinese troop movements along the Myanmar border. But they concluded they were unrelated to events in Myanmar, formerly known as Burma.