The flames could be seen as far away as the capital, Amman, 35km (22 miles) to the southwest.
Amjad Adailah, spokesman for Jordan's government, said "the blasts occurred in a warehouse containing unusable mortar bombs belonging to the armed forces".
He made it known that no injuries have been recorded so far.
Additionally He said, "initial investigations show the explosion was caused by an electric circuit in army ammunition depots that are in an isolated and unpopulated area and under camera surveillance".
Following the explosions, security forces sealed off Zarqa, a sprawling industrial city of 1.5 million people, and prevented traffic from leaving or entering.
A committee has been set up to determine the causes of the explosion.
SOURCE: Aljazeera
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