A DOD-contracted aircraft flying an "intelligence, surveillance, and reconnaissance" mission crashed in the Philippine Province of Maguindanao del Sur, killing all four on board, U.S. Indo-Pacific Command said Thursday.
The victims included one U.S. military service member and three defense contractors, according to federal officials.
"The incident occurred during a routine mission in support of U.S.-Philippine security cooperation activities," U.S. Indo-Pacific Command said in a statement, noting that the aircraft was requested by Filipino allies.
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The cause of the crash is under investigation, according to federal officials.