A massive blast on a container ship in Dubai Wednesday night was felt across the city and sent a huge fireball into the sky. CNN personnel in the emirate say the explosion was felt more than 10 miles from the Jebel Ali Port , which is the biggest in the region and an important port of call for US warships. There were no immediate reports of casualties and the extent of damage to the port is unclear, the AP reports. The Dubai government's media office says the explosion was caused by a fire on the ship. The office says firefighters have brought the blaze under control and port officials say they are "taking all necessary measures to ensure that the normal movement of vessels continues without any disruption." (More Dubai stories.)