Civil defense forces in Yemen's port city of Aden fought to extinguish a fire at an oil refinery on Friday, sparked hours earlier by an explosion, the cause of which was still unknown, the refinery company said. There were no reports of casualties. Separately, Saudi state television reported that the Saudi-led military coalition fighting the Iran-allied Houthi group had destroyed a communication and control center the Houthis used to direct their unmanned aircraft. It did not give further details. A day earlier the Houthis launched a drone attack on a military parade in Lahaj, a province next to Aden, killing several people. Aden is under the control of an internationally recognized government, which, backed by a Saudi-led and U.S.-backed coalition, is fighting a nearly four-year-old war against the Houthis.