TAIPEI (Taiwan News) — A Patriot PAC-2 missile exploded four seconds into its flight during military drills in Pingtung on Wednesday, reports said.

The US-made missile was one of several fired during two days of exercises off Taiwan’s southeast coast. The explosion occurred at 5:34 a.m., but another Patriot was launched successfully just one minute later, according to the Liberty Times.

The military did not confirm details of the incident but said an investigation is underway, with results to be used for future improvements, per CNA.

The drills began at 3 a.m. with the Navy firing two Hsiung Feng II anti-ship missiles that hit their targets. At 4 a.m., two Sky Sword II missiles were also launched successfully. Following the Patriot test, the military fired Sky Sword III anti-air missiles without incident.

Patriot PAC-2 missiles were first delivered to Taiwan in 1996. A similar incident occurred in August 2023, when a missile of the same type detonated mid-air over Pingtung County.