The search for a man seen jumping off a ship in the commercial port in Portsmouth Harbour has been called off.
Coastguards said two men were thought to have stowed away on a refrigerated cargo ship from the Caribbean and jumped overboard at about 1810 BST.
One man has been rescued from the water but the other is still missing.
The BBC understands the men had arrived in the city on Sunday as stowaways on the same vessel and were refused entry before being put back on the ship.
The men are thought to be from the Dominican Republic and were onboard the Timor Stream, operated by Geest, which was carrying fruit and other goods from the eastern Caribbean.
Having been discovered by the ship's crew on Sunday, they were handed over to immigration authorities, sources have told the BBC.
On failing to provide the relevant documentation, they were refused entry to the UK, and put back on the same boat, which is due to leave for the Caribbean on Tuesday.
The man who was rescued is being interviewed by immigration officials.
The Solent Coastguard helicopter, the Portsmouth coastguard rescue team and the Gosport Inshore Rescue boat searched without success around the ferry port for the second man.
The search was stood down due to fading light.
Colin Griffiths, Solent Coastguard watch manager, said earlier: "We are very concerned for the safety of the missing man."
Canoes had also been deployed to search underneath pontoons for the man and the Ministry of Defence police launch was involved in the operation.
The Marine Accident Investigation Branch has been informed.
Hampshire police said they were assisting the UK Border Agency in the operation.