Grimaldi Lines, which operates the vessel, said there were no reports of injuries.
Essex Police said Sunday the four were charged with "affray", a crime defined as using of threatening to use violence in a way that makes by-standers fear for their safety.
But earlier on Friday (Dec 21), they managed to free themselves and the 27 crew members have since locked themselves in on the bridge.
"After that, another helicopter with six policemen came and they kept them in a cabin waiting for the vessel to get in to Tilbury".
Google in China the plug — Search engine Dragonfly
Although the Google Play store is banned in China, plenty of Google apps are available on iOS and Chinese Android app stores. This team was kept in the dark about what the developer team was doing, and only found out after the media reported on it.
SPECIAL force commandos abseiled their way onto a cargo ship near Tilbury after stowaways turned pirates allegedly took over armed with iron bars.
The Italian-flagged ship was carrying containers and machinery.
The company's spokesman Paul Kyprianou told Sky News: "The vessel was coming from Nigeria..."
Last night, Essex police said: 'We have now secured a vessel in the Thames Estuary. Police have not commented on what took place on board the ship to lead to their intervention.
The defendants, all of no fixed address, were remanded in custody, to appear at the same court on December 31.