TAIPEI: China fired multiple missiles around Taiwan on Thursday as it launched unprecedented military drills a day after a visit by US House of Representatives Speaker Nancy Pelosi to the self-ruled island that Beijing regards as its sovereign territory.

Soon after the scheduled start at 0400 GMT, China’s state broadcaster CCTV said the drills had begun and would end at 0400 GMT on Sunday. It said the exercises, the largest ever by China in the Taiwan Strait, would include live firing on the waters and in the airspace surrounding Taiwan.

China’s Eastern Theatre Command said it had completed multiple firings of conventional missiles on waters off the eastern coast of Taiwan as part of the planned exercises.

The last time China fired missiles into waters around Taiwan was in 1996.

Taiwan’s defense ministry said several Dongfeng missiles had been fired in waters to the northeast and southwest of the island.

Two missiles were also launched by China near Taiwan’s Matsu islands, which lie off the coast of China, at around 2 p.m. local time (0600 GMT) in the direction of drill zones announced by China, according to an internal Taiwan security report seen by Reuters and confirmed by a Taiwan security source.

Taiwan officials have said the drills violate United Nations rules, invade Taiwan’s territorial space and are a direct challenge to free air and sea navigation.

China is conducting drills on the busiest international waterways and aviation routes and that is “irresponsible, illegitimate behavior,” Taiwan’s ruling Democratic Progressive Party said.

Taiwan’s cabinet spokesman, expressing serious condemnation of the drills, said also that websites of the defense ministry, the foreign ministry and the presidential office were attacked by hackers.

Chinese navy ships and military aircraft briefly crossed the Taiwan Strait median line several times on Thursday morning, a Taiwanese source briefed on the matter told Reuters.

By midday on Thursday, military vessels from both sides remained in the area and in close proximity.

Taiwan scrambled jets and deployed missile systems to track multiple Chinese aircraft crossing the line.

“They flew in and then flew out, again and again. They continue to harass us,” the Taiwanese source said.

China, which claims Taiwan as its own territory and reserves the right to take it by force, said on Thursday its differences with the self-ruled island were an internal affair.

“Our punishment of pro-Taiwan independence diehards, external forces is reasonable, lawful,” China’s Beijing-based Taiwan Affairs Office said.

China’s Foreign Minister Wang Yi called Pelosi’s visit to Taiwan a “manic, irresponsible and highly irrational” act by the United States, state broadcaster CCTV reported.

Wang, speaking at a meeting of Southeast Asian foreign ministers in Phnom Penh, Cambodia, said China had made the utmost diplomatic effort to avert crisis, but would never allow its core interests to be hurt.

The foreign ministers in a statement had earlier warned that volatility caused by tensions in the Taiwan Strait could lead to “miscalculation, serious confrontation, open conflicts and unpredictable consequences among major powers.”

Unusually, the drills in six areas around Taiwan were announced with a locator map circulated by China’s official Xinhua news agency earlier this week — a factor that for some analysts and scholars shows the need to play to both domestic and foreign audiences.

On Thursday, the top eight trending items on China’s Twitter-like Weibo service were related to Taiwan, with most expressing support for the drills or fury at Pelosi.

“Let’s reunite the motherland,” several users wrote.

In Beijing, security in the area around the US Embassy remained unusually tight on Thursday as it has been throughout this week. There were no signs of significant protests or calls to boycott US products.

“I think this (Pelosi’s visit) is a good thing,” said a man surnamed Zhao in the capital’s central business district. “It gives us an opportunity to surround Taiwan, then to use this opportunity to take Taiwan by force. I think we should thank Comrade Pelosi.”