Migrants on a humanitarian ship off the Italian coast had to be chased down after they jumped into the sea in a desperate attempt to reach land.
Four of them put on life jackets and jumped into the water as two crew members swam after them and brought them back to the boat.
It comes as the group that runs the ship warned of an “extreme humanitarian emergency” on board.
The boat is carrying 107 migrants rescued near Libya two weeks ago and has been anchored near the island of Lampedusa trying to get permission to dock.
Italy’s anti-immigration interior minister Matteo Salvini has refused them permission but on Saturday had to let minors disembark on the orders of Italy’s prime minister.
Spain’s prime minister has offered to break the stand-off and let the ship dock in its southern port of Algeciras.
Pedro Sanchez said the offer reflected the dire conditions on board – where violence has started to break out and there are just two toilets.
Mr Sanchez also described Mr Salvini’s refusal to let the boat in as “inconceivable”.
However, the group that operates the ship, Barcelona-based Open Arms, rejected Spain’s offer saying it is too far and the situation is at breaking point.
“There is anxiety, bouts of violence, control is becoming increasingly difficult,” said spokeswoman Laura Lanuza.
“To embark on a six day sailing with these people on board who are at the very limit of their possibilities would be crazy. We can’t put their health and lives at risk.”
Five other countries have also offered to let the ship dock
Mr Salvini has built his reputation on being tough on migrants and on Sunday told the ship to leave Italian waters and go to Spain.
He tweeted that the boat was refusing to move “just to provoke me and Italy.”
Open Arms has accused Mr Salvini of using the situation for “xenophobic and racist propaganda” and says the people on board are victims of abuse, rape and torture.
The situation on the boat – which has now been at sea for 17 days – was highlighted by US actor Richard Gere, who recently went on board to give the migrants food and supplies.
People are continuing to try to cross the sea from North Africa to Europe.
Attempted crossings this week include four boats carrying 278 people picked up by the Libyan coastguard and 330 people seized by Turkish authorities as they tried to get to the Greek island of Lesbos.
However, the numbers are much lower than the peak of the migrant crisis a few years ago.
More than 4,200 migrants have so far arrived in Italy by sea this year, says the UN Refugee Agency. Most of them are from Tunisia (858) and Pakistan (620).
Some 575 are also dead or missing on the North Africa-Italy route, up until end of July.
Across the Mediterranean region, the figure is 838 – just over half of what was recorded in the same period in 2018.