Greek commandos on board ship with 'seized' aid workers
Greek commandos have boarded a ship outside Piraeus Harbour in Athens where a group of aid workers claim they have been held captive since Thursday.
The captain of Strofades IV took the volunteers to his native Greece after leaving Derna Harbour in Libya.
But ship managers said the "activists" jumped on board and the captain set sail to stop others boarding amid fears they would divert the ship to Gaza.
The Foreign Office is investigating the reports involving seven UK aid workers.
The British Embassy in Athens has also told the BBC it was in contact with the ship's owners and the Greek authorities, and was trying to ensure a safe resolution.
The ship is being held outside Piraeus Harbour - the main port in Athens.
Ellie Merton, the London liaison for the group, also told the BBC: "The group is in a secure situation with the Greek navy - who were allowed to go on the ship."
She clarified earlier reports that the group, part of the Road to Hope aid convoy, had been held at gunpoint by the soldiers and said: "There are guns there but they are not being held at gunpoint."
Mr Sharif revealed in an update on the social networking site Facebook that the soldiers searched the group.
Ms Merton added: "The guys were initially really alarmed. They had been on the ship for 30 hours and then the commandos came on and they felt as if they were being treated like suspects.
"But the commandos are helping the ship go through the busy port. We are confident about the way the Greek authorities are behaving."
The other British nationals on-board include Mustapha El-Guerbouzi, Raheal Parveez, Yunus Malik, Nagib Elgarib Elbarrami, all from London, and Kieran Turner, from Liverpool.
Khalid Mohamed Omar Ali, whose hometown has not yet been reported, is also from the UK.
Algerian Aziz Mekkati, and David Callender and Kenneth O'Keefe from Ireland are also on-board.
There are also seven Libyans on the boat. They are said to include customs inspectors, border police and the harbour manager for Derna Port in Libya.
Mr Sharif, who is also known as Tox, was also on the Gaza-bound aid ship Mavi Marmara which tried to breach an Israeli naval blockade in May this year.
The British Foreign Office said it was aware of the incident and had been in close contact with the convoy's organisers.
"We have been informed that the ship has now anchored outside of Piraeus port, Greece, and we understand docking will take a few hours," it said in a statement.
"British Embassy staff will provide consular assistance to the British nationals on board, if requested.
"We remain in close contact with the Greek authorities, and our priority remains that there is a safe resolution to this incident."
Ms Merton said the captain became irritable in the port area over payments but the group had given the money in cash to a shipping agent.
She said the captain appeared to fear that the agent would not pay him the £56,000 ($90,000) fee for the trip to Gaza.
Text messages sent from the group to Ms Merton on Thursday as they were taken to Greece suggest that the volunteers were kept in one small cabin.
In one message, Mr Turner said: "Initially we were stopped from moving around the ship and had to stay in the bottom of the lower deck.
"Eventually we just walked through to the crew quarters, and they've let us occupy their small smoking room.
"At least we are safe and in the dry, and it has a couch so we can try to sleep. We've been given one meal, of sorts, since the ship left Derna. We've got access to water, but it's not drinking water."
But the Greek managing company behind the Strofades IV has denied reports the aid workers were held against their will.
Ionian Bridge Shipmanagement said 10 of around 150 activists had jumped on board the ship at Derna, forcing the captain to set off to prevent all of them boarding and taking over the ship.
It said the captain was afraid more would board and divert the ship to Gaza, which is under an Israeli naval blockade.
The company said in a statement: "We never intended to transfer the activists, because we realised they wanted to lead the ship not to El Arish but Gaza, to break the embargo and pitch us against the Israeli navy. We wanted to leave, fearing for our lives."
About 70 other volunteers on the convoy, including four people from Londonderry, remain stranded in Libya after the captain stopped them from boarding his ship.
Betty Doherty, from Derry, said the group's passports were taken from them.