China sent 15 military aircraft into Taiwanese airspace between mainland Taiwan and the Taiwan-controlled Pratas Islands in the South China Sea on Sunday, Taiwan's Defense Ministry said.

A total of six J-10 fighters, four J-16s, two SU-30s, a Y-8 reconnaissance aircraft and two Y-8 anti-submarine aircraft, were sent by China, the ministry said in a statement.

It follows China sending eight nuclear-capable bombers and four fighter jets into the same airspace on Saturday.  

Taiwan's air force was sent up to respond, the statement said.

"Airborne alert sorties have been tasked, radio warnings issued and air defense missile systems deployed to monitor the activity," said the ministry.

China, which continues to claim Taiwan as its own territory, in recent months has conducted almost daily flights over the waters between the southern part of Taiwan and the Pratas Islands.

However these flights have generally consisted of only one or two reconnaissance aircraft. The presence of so many Chinese combat aircraft on this mission — including an anti-submarine aircraft, eight H-6K bombers, and four J-16 fighter jets — is unusual.

A map provided by Taiwan's Defense Ministry showed that the Chinese aircraft flew over the same waters where the most recent Chinese missions have been taking place, well away from mainland Taiwan.

Response from Washington

News of the incursion brought a swift statement from the US State Department, urging China to stop pressuring Taiwan while reaffirming its commitment to the nation.

"We urge Beijing to cease its military, diplomatic, and economic pressure against Taiwan and instead engage in meaningful dialogue with the nation's democratically elected representatives," said State Department spokesman Ned Price.

"We will continue to assist Taiwan in maintaining a sufficient self-defense capability," he continued.

Though there was no immediate comment from China, in the past leaders there have said it will continue to carry out exercises to defend the country's sovereignty and security.

Early test for Biden

The incursion on Saturday occurred just days after Joe Biden assumed the US presidency.

Emily Horne, spokeswoman for the White House's National Security Council, said US commitment to Taiwan remains "rock-solid" after the island's de facto ambassador in Washington, Hsiao Bi-khim, attended Biden's swearing-in on Wednesday.

mb/aw (dpa, Reuters)