Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: (CNN) An Emirati aid ship headed for war-torn Yemen was hit by an airstrike launched by Houthi rebels, according to official UAE state news agency, WAM. A Houthi spokesperson told CNN the Iranian-allied group was responsible for Saturday's attack, which occurred as the vessel headed for the port city of Aden. The Saudi-led Arab coalition, which has been fighting in support of the Yemeni government under President Abd Rabbuh Mansur Hadi, called the attack a "dangerous indication" and launched a rescue mission for those aboard the stricken ship. The vessel, owned by the UAE's National Marine Dredging Company, was reportedly delivering medical aid and other supplies when it came under fire in the Bab al-Mandab Strait -- which lies between the southern tip of Yemen and Djibouti and Eritrea in the Horn of Africa -- according to the WAM report.Saudi-led Arab coalition called the attack a "dangerous indication"Vessel attacked en route to Aden, which is under government controlHouthi rebels control the country's capital, Sanaa 
 Question:''This comes as a serious indicator to confirm the orientation of these militias to carry out terrorist operations targeting the international navigation and relief ships in Bab al-Mandab Strait," the coalition said in a statement posted on _.

WAM