MANILA, Oct 24 — Two military planes crashed mid-air during training at an air base in the Philippines, killing four pilots, the air force said Saturday.

The SF-260 single propeller planes crashed at Fernando Air Base, south of Manila, on Friday afternoon.

“Both aircraft went down within the base perimeter, with no other casualties reported,” Philippine Air Force spokesman Colonel Alvin Capinguian said in a statement.

An investigation was opened to determine the cause of the mishap, and Capinguian said the air force’s fleet of SF-260s has been temporarily grounded as a precaution.