A vessel sailing off southern Yemen reported an explosion nearby on Sunday, a British maritime security agency said, the latest incident as Huthi rebels have attacked shipping on the vital Red Sea route. The United Kingdom Marine Trade Operations (UKMTO) said a commercial ship experienced an explosion in close proximity, causing no casualties or damage. The blast occurred 85 nautical miles east of Aden, Yemen, and the vessel was proceeding to its next port of call. The Huthis, backed by Iran, have launched dozens of missile and drone strikes on shipping in the Red Sea and the Gulf of Aden in the past four months. The United States has been conducting strikes against Huthi targets in Yemen, and shipping insurance costs have increased due to the frequent attacks.