Following the September 11 Attacks in September 2001, the United States of America launched the War on Terror to depose the Taliban's regime in Afghanistan. The attack had initially been carried out by Al-Quaeda which was founded by Osama bin Laden. Initially, bin Laden denied involvement but he later abandoned his denials.
For the next 10 years, Osama was running from the Americans who were on a manhunt for him and it wasn't until August 2010 when it was discovered that he was in Pakistan. On 2 May 2011, the United States Navy SEALS broke into the compound where bin Laden had been hiding in Abbottabad, Pakistan and killed him. With his body being rejected by numerous countries, it was decided to avoid his grave from becoming a terrorist shrine that he would be buried at sea. His body was prepared in accordance with Islam laws and was dumped in a weighted bag into the sea.
In a similar way, the leader of ISIS, Abu Bakr al-Baghadadi was also buried at sea after his death in 2019.