A cadet died, and seven cadets and their trainer were injured in an explosion of a grenade allocated for training at the King Abdulaziz Military College near Riyadh, according to Saudi News Agency on Tuesday. Earlier reports put the number of injuries at ten, and among them one in severe conditions. The injuries of others are not considered as life-threatening, the Saudi Defence Ministry was quoted by the Saudi assaying. The ministry meanwhile said that an investigation had been launched into the \"accidental\" incident. According to a report by e-paper Elaph, the college had ordered a testing of all ammunitions allocated for training. The King Abdulaziz Military College, the oldest military colleges in the oil-rich country, is the first choice for cadets from ground forces and military police. It also has students from other Gulf and Arab countries. The nationalities of the cadets in the accident were not revealed.