MANILA— Two Philippine jets intercepted an "unknown aircraft" as it flew close to the country's air space off Pangasinan on Sept. 2, forcing the plane to change direction, the Philippine Air Force (PAF) said Saturday.

PAF said two FA-50 jets were sent a "scramble" order to intercept an unknown plane around 9:36 a.m. on Thursday after the Philippine Air Defense Control Center detected it within the Philippine Air Defense Identification Zone (PADIZ) some 120 nautical miles north west of Bolinao, Pangasinan.

"The unidentified aircraft was heading towards Philippine airspace. Coordination with the CAAP (Civil Aviation Authority of the Philippines) classified it to be an unknown track of interest," the Air Force said.

Upon dispatch, the two jets spotted the aircraft at 21,000 feet flying at 265 knots going north east, and caught up with the plane.

The plane then sped off and moved away from the path towards Philippine airspace.

"At about 4 minutes into the intercept, the unknown aircraft changed direction towards the north and increased its speed to 400 knots and headed away from the Philippine airspace," the Air Force said in a statement.

The entire intercept lasted 9 minutes and was terminated at 9:45 a.m.

PAF spokesperson Lt. Col Maynard Mariano said the Philippine jets did not get to identify whether the plane was civilian or military.

"No visual identification was made, the aircraft changed direction and speed moving away from our airspace, but our sensors were tracking the said aircraft," he told ABS-CBN News.

He said the flagged plane also did not respond via radio.

"There was no radio response coming from the unknown aircraft," he said.

The entire intercept lasted 9 minutes and was terminated at 9:45 a.m.

Mariano said there have been previous intercepts of unauthorized planes venturing into Philippine airspace, but said he could not release other details, including the frequency of such incidents.

The Philippines acquired FA-50 jets from South Korea starting 2015 in a boost to its air defense capabilities amid security concerns, particularly unresolved disputes in the South China Sea.

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