Four Taiwanese F-16 fighter jets on a training mission at Luke Air Force Base in Arizona flew back to Taiwan on Tuesday after a stopover in Honolulu, according to a military source.

The F-16s landed at Hualien Air Force Base in eastern Taiwan around 3:40 p.m., a military official familiar with the matter told CNA.

Three of the four fighter jets were single-seat F-16As, with the serial numbers 6690, 6603, and 6670, while the other was a twin-seat F-16B with the serial number 6807, the official said, noting that the planes had been refueled in midair several times before reaching Taiwan.

No further details were given and the Air Force declined to comment publicly on the matter.

According to sources, the four F-16s were the last of 11 F-16A/Bs training with Luke Air Base’s 21st Fighter Squadron to return to Taiwan.

The training mission is part of a Taiwan-U.S. program that began in the 1990s when Taiwan purchased its first batch of the jets from the U.S.

The jets that flew back to Taiwan are set to be upgraded into the more advanced F-16V format as part of a retrofitting project launched by the Air Force in 2016, according to sources familiar with the matter.

The return of the four fighter jets on Tuesday came after six F-16 fighter jets belonging to Taiwan’s Air Force flew back to Taiwan on June 10. Another jet made a hard landing at an airport in Honolulu due to a landing gear malfunction. No one was injured.

Source: Focus Taiwan News Channel