The explosion was a "normal accident" in a container holding flammable material, DMO Director General Mona Al Marri told Saudi-owned Al Arabiya television channel.
Arabiya cited Dubai police as saying the cause may have been "friction or high temperatures" during the hot summer months.
Witnesses in residential areas between 15 km and 22 km from Jebel Ali had heard the blast.
DMO said in a statement that there were no casualties or injuries. It posted footage of water being pumped to douse flames and debris at the scene.