LONDON (AP) — Seven stowaways seized when British naval special forces stormed an oil tanker in the English Channel have been arrested on suspicion of hijacking, police said Monday.

Hampshire Police said the men, believed to be from Nigeria, were being held at several police stations on suspicion of “seizing or exercising control of a ship by use of threats or force.” They have not been charged.

Police said the 22 crew members of the Nave Andromeda were “safe and well” after the raid, which unfolded after darkness fell on Sunday. Special Boat Service commandos were lowered by rope from helicopters onto the tanker, whose crew had locked themselves in a secure part of the ship known as the citadel. Within minutes, the stowaways were in custody.

Maritime tracking websites showed the ship reached port in Southampton, on England’s south coast, early Monday.

Police said officers were speaking to crew members to determine exactly what had happened.

The ship had left Lagos, Nigeria, on Oct. 6 and had been due to dock in Southampton on Sunday.