Seven men detained after special forces stormed an oil tanker off the Isle of Wight have been released on bail by the police, but remain in Border Force custody.
The Nigerian nationals were arrested on suspicion of seizing or exercising control of the Nave Andromeda.
The Special Boat Service landed on the ship when the stowaways reportedly became violent on Sunday night.
The tanker later docked in Southampton with all 22 crew members reported safe.
Hampshire Constabulary was granted extra time to question the suspects following their arrests on Monday, but released them on bail late on Thursday.
While the investigation continues, the men will remain detained under Border Force powers.
The Southampton-bound ship had left Lagos on 5 October.