Four stowaways from Nigeria have been arrested in the United Kingdom after special forces stormed a cargo ship off the country’s coast.

The stowaways, who are obviously migrants had threatened staff on-board.

Special Boat Service (SBS) operatives from Sabre Squadron fast-roped from helicopters on to the ship, which had been sailing in the Thames Estuary, Sky News reported.

The operation lasted around 25 minutes and no one on-board was injured.

Essex Police said the vessel was taken to the Port of Tilbury and four men have been arrested under the Immigration Act.

The ship arrived at the Port of Tilbury in the early hours of Saturday at just after 4.20am.

Officers boarded the 236-metre long cargo ship, called the Grande Tema, shortly after 11pm on Friday.

Its operator, Grimaldi Lines, had earlier reported that four stowaways armed with iron tubes had called for the crew to navigate closer to the coast.

The company’s spokesman Paul Kyprianou told Sky News: “The vessel was coming from Nigeria… They managed to escape from the cabin and started threatening the crew, requesting to have the vessel navigate very close to the coast.

“We understand they wanted to jump and reach the British coast.”

He added that the crew locked themselves in the bridge of the vessel after the migrants had picked up potentially harmful objects.

“They managed to get whatever they could find on the vessel… pieces of iron, tubes and things like that and this is what they used in order to threaten,” Mr Kyprianou said.

The vessel had been travelling eastwards through the English Channel when the migrants were discovered on Friday morning.