All the over 150 migrants aboard a rescue boat funded by British street artist Banksy have been transferred to another rescue ship, the Louise Michel crew said on Sunday.
After sending an urgent call for help, the Louise Michel transferred them on the Sea-Watch 4 vessel.
The German rescue ship is now housing around 350 migrants and urgently looking for a port where it can disembark.
Another rescue vessel also needs help. Some 27 migrants and refugees, including a pregnant woman and children from Libya, have been aboard the Maersk Etienne since they were rescued on August 5.
The UN Refugee Agency said on Sunday almost 400 refugees and migrants rescued in the Mediterranean must be allowed to disembark safely.
The Louise Michel crew said some of them suffer from "dehydration, traumatic injuries, hypothermia and fuel burns."
The Italian coastguard on Saturday rescued another 49 people from the Louise Michel.
The vessel had called for urgent help after assisting a boat in the Mediterranean that was carrying around 130 migrants including at least one who died.
The crew on the Louise Michel tweeted saying that the people they had rescued had experienced extreme trauma and needed vital assistance as they're unable to move and that nobody is coming to their aid.
The Louise Michel, named after the 19th century French anarchist, was thought to be around 90 kilometres from the Italian island of Lampedusa.
The crew said the Italian Coastguard had evacuated 49 of its "most vulnerable guests" from the ship as well as the body of the deceased person.
"May he rest in peace," they said.
More than 100,000 migrants tried to cross the Mediterranean last year from North Africa with more than 1,200 dying in the attempt, according to the International Organization for Migration.
Painted in hot pink and white, the Louise Michel features a Banksy artwork depicting a girl in a life vest holding a heart-shaped safety buoy. The 31-metre motor yacht, formerly owned by French customs authorities, is smaller but considerably faster than other NGO rescue vessels.
Banksy's decision to fund the high-speed boat follows a body of work by the artist that has levelled scathing judgements on Europe's halting response to the migrant crisis.
The Louise Michel left the Spanish port of Burrinia in secret earlier on August 18th.