In the most recent case, a group of Taiwan jets allegedly tried to cross the middle line in the Taiwan Straits, but were turned back by Chinese aircraft on patrol, the Beijing-backed Wen Wei Po newspaper said.

"Taiwan attempts to create military incidents have gone on without interruption," the unidentified official told the Hong Kong paper.

"If Taiwanese military aircraft cross the middle line and enter into our airspace, we will use military force to smash them or force them to land at mainland bases," he said.

The stark warning came as China kept up its strident rhetoric against Taiwan at the start of a new four-year term for the island's President Chen Shui-bian, who is seen by Beijing as a dangerous advocate of independence.

The paper cited an incident said to have taken place recently, when a group of Taiwan aircraft, including US-built F-16s, were heading for the middle line in the Taiwan Straits.

Although they were flying low to avoid detection, they were spotted by mainland radars, and Chinese jets on patrol in the area were dispatched to block their entry, the paper said.

"We will resolutely hit at Taiwan attempts to create incidents," the unnamed Chinese official said. "We will absolutely not tolerate it."

According to the existing rules of engagement, if Taiwanese combat aircraft do cross the middle line, China's military is to adopt "destructive" force, the paper said.

That force is to be applied not just against the intruding aircraft, but also against support facilities on Taiwan, according to the report.

"If foreign military forces seek to interfere in the clash, it will be seen as foreign intrusion, and we will resolutely counterattack," the unnamed source said.

WAR.WIRE