House Speaker Nancy Pelosi (D-CA) arrived in Taiwan on Tuesday for a visit that sparked ominous warnings from both the White House and Chinese government—and military exercises by both Chinese and Taiwanese forces. Her plane landed shortly before 11 p.m. local time. She is expected to meet with President Tsai Ing-wen, lawmakers, and human rights activists in the first such trip to the contested island by a high-ranking U.S. politician in 25 years. In a statement, she said the visit “honors America’s unwavering commitment to supporting Taiwan’s vibrant democracy” and that it “in no way contradicts longstanding United States policy.” Beijing had warned that it would respond with “forceful measures” if a U.S. rep were to visit the self-governing island that China claims as its own territory. President Joe Biden has said the visit is “not a good idea,” even as the White House noted it’s up to Pelosi. Moscow also condemned the visit, with Kremlin spokesman Dmitry Peskov calling it a “pure provocation” that is likely to raise tensions in the region. Taiwanese media reported that the military was put on a “strengthened” state of readiness, while China also announced additional military drills and, according to Reuters, sent fighter jets close to the island. Just before her arrival, Taiwan said its government websites were also hit by a cyberattack.