The twelve-hour hijacking of a cargo ship in the Thames Estuary by illegal migrants was brought to a dramatic end by a Special Boat Service (SBS) boarding, according to reports.

Commandos from the elite Royal Navy unit, regarded as something of a sister unit to the British Army’s Special Air Service (SAS), abseiled onto the Grande Tema some time between 11 p.m. and midnight on Friday, The Sun reports

The 236-metre Grimaldi shipping line vessel had been circling in the iconic Thames Estuary north-east of Margate, Kent, for hours, after a group of would-be illegal migrant stowaways who had been discovered some days earlier escaped from their quarters, armed themselves with iron bars and other makeshift weapons, and threatened the crew with violence.

A spokesman for the shipping line told Sky News that crew members were able to lock themselves inside the bridge, refusing the migrants’ demands to bring the Grande Tema closer to shore so they could make a swim for it — a manoeuvre which would have been extremely dangerous, given the container ship’s enormous size.

The authorities would not comment on the reported involvement of special forces in bringing the incident to an end, but Essex Police have confirmed the vessel “was boarded and secured shortly after 11 p.m. on Friday December 21 and [has] now be brought safely into dock at the Port of Tilbury.”

The stowaways, who are thought to have infiltrated the Grande Tema at Lagos, Nigeria, have been detained under the Immigration Act.

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