On 21 December 2018, there was an incident aboard the container ship Grande Tema in the Thames Estuary. Four stowaways, who had travelled aboard the vessel from Lagos, Nigeria, demanded to be let off near the British shore. The crew of the Grimaldi Group ship refused, and when the stowaways made threats, they barricaded themselves on the bridge. The British authorities were alerted, and following failed negotiations, special forces operatives from the Special Boat Service landed on the vessel and detained the stowaways. The men were later found guilty of affray and making threats to kill and received prison sentences.