TAIPEI, Taiwan (AP) — Chinese warplanes tailed a U.S. military aircraft through the sensitive Taiwan Strait on Tuesday, China’s military said.

The U.S. aircraft was a P-8A Poseidon patrol and reconnaissance plane, capable of conducting long-range anti-submarine warfare, according to a statement by the People’s Liberation Army’s Eastern Theater Command.

Chinese military forces “organized warplanes to tail and monitor the U.S. aircraft’s flight and handled it in accordance with the law,” said Li Xi, a senior colonel and spokesperson for the command.

“Theater command troops will remain on constant high alert and resolutely safeguard national sovereignty and security as well as regional peace and stability,” he added.

The U.S. Navy didn’t immediately comment on the incident.

China claims the self-ruled island of Taiwan as its own territory and bristles at other countries’ patrolling the body of water separating it from the island.

On Friday, Germany sailed two warships through the Taiwan Strait in its first transit of the disputed waters in more than two decades, drawing criticism from Beijing.

In 2001, a U.S. surveillance plane and a Chinese navy fighter collided mid-air near the Chinese island province of Hainan, resulting in the Chinese pilot’s death. The U.S. said its plane was in international airspace and the accident was the result of reckless flying by the Chinese side.