Taiwan's defense ministry has said it spotted 28 Chinese air force planes in its air defense zone on Wednesday morning, part of what Taipei calls regular harassment by Beijing amid heightened tensions across the strait.

Democratically-governed Taiwan, which China views as its own territory, has complained in recent years of stepped up Chinese military activities near the island as Beijing seeks to assert its sovereignty claims.

Taiwan's defense ministry said that beginning at around 6 a.m., Chinese war planes, including J-10 fighters, had flown into the southwestern corner of the island's air defense identification zone, or ADIZ.