World NEWS: CHAD.
The nine tons of mines had been cleared from heavily mined areas of northern Chad and were being held in the oasis of Ouadi Doum,about 560 miles from N'Djamena.
The cause of the explosion is not clear.
Parts of northern Chad were heavily mined following Libya's invasion of the African country in 1980. The conflict between Chad and its northern neighbour lasted until 1987.