Four men have been detained after stowaways reportedly tried to take control of a ship in the Thames Estuary.

Essex Police boarded the container vessel, the Grande Tema, at around 11pm last night.

A 12-hour standoff between crew and the suspected migrants ended after a Special Boat Service squadron abseiled onto the ship.

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A number of unmarked vehicles were seen on Marine Drive, Margate, near where the Grande Tema had been sailing at around 8.45pm last night.

It is understood the stowaways wanted the vessel, which arrived at the Port of Tilbury just after 4.20am, to get closer to the Kent coast and were armed with iron tubes.

The force was called at around 9.15am on Friday morning after concerns were raised for the crew's safety.

Speaking yesterday, Paul Kyprianou from the Grimaldi Lines, which owns the vessel, said: "They are armed with iron bars and they have been threatening the crews this morning requesting they must get close to the shore.

"The crew members are locked on the bridge and are in direct contact with the UK authorities."

The migrants are thought to have been discovered on the ship four days ago.

Mr Kyprianou added: "They were put in a cabin, and given accommodation, food and anything needed.

"Obviously they had to be guarded in order to avoid any reaction from their side, which unfortunately took place this morning."

"They are armed with iron bars and they have been threatening the crews this morning requesting they must get close to the shore..." - Paul Kyprianou, Grimaldi Lines

The four men are believed to be from Nigeria.

Essex Police say the ship is now secure and there are no reports of injuries.