TAIPEI (Taiwan News) — The Ministry of National Defense (MND) announced that two Chinese balloons were detected crossing the Taiwan Strait median line on Sunday (Dec. 17).

The MND said that two Chinese balloons were detected at 9:03 a.m. and 2:43 p.m., respectively, Sunday after crossing the Taiwan Strait median line 110 nautical miles (204 km) northwest of Keelung at an altitude of approximately 27,000 feet (8,230 m). The balloons headed east and disappeared at 9:36 a.m. and 4:35 p.m.

In addition, the MND also announced that six People's Liberation Army aircraft and two naval vessels were tracked around Taiwan between 6 a.m. Sunday and 6 a.m. Monday (Dec. 18), with one plane entering the air defense identification zone (ADIZ) in the southwest.

When asked by Taiwan News whether the balloons were used for surveillance, an MND spokesperson said the preliminary assessment is that they are weather balloons.