Amateur video footage shows the JAS 39 Gripen jet maneuvering over the Hat Yai air base in southern Thailand when it suddenly lost altitude and crashed in a ball of fire away from spectators.
The Ministry of Defense is investigating the cause of the crash today.
Deputy government spokesman Werachon
Sukondhapatipakerachon says Prime Minister Prayuth Chan-ocha expressed condolences to the pilot's family.
Children's Day is usually observed with public outings at military bases.