More than 2,000 asylum seekers trying to reach Europe were plucked from the Mediterranean on Friday in a series of dramatic rescues.
An Italian coast guard spokesman said 19 rescue operations by the coast guard or ships operated by non-governmental organisations had saved a total of 2,074 people on 16 overcrowded rubber dinghies and three small wooden boats.
One person was found dead, the spokesman said.
The Doctors Without Borders (MSF) boats Prudence and Aquarius rescued some 1,145 people from nine different dinghies in non-stop operations.
MSF later posted a video showing women singing with happiness after their rescue.
The rest of the asylum seekers were picked up by the coast guard, the Phoenix - run by the Maltese Migrant Offshore Aid Station (MOAS) - the German NGO Sea Eye and the German Jugend's Iuventa.
"In 19 years of covering the migration story, I have never experienced anything like today," said Reuters news agency photographer Darrin Zammit Lupi, who was aboard the Phoenix.
In one operation, it rescued 134 people, all from sub-Saharan counties, he said.
Friday's rescues come a day after a shipwreck left at least 97 migrants feared drowned off Libya.
According to the International Organisation for Migration, nearly 32,000 asylum seekers arrived in Europe by sea so far this year. More than 650 have died or are missing.
EU's border control agency Frontex has accused donor-funded vessels of doing more harm than good by sailing off Libya and acting "like taxis", and Italian prosecutors have suggested they may have links with traffickers - a charge they have fiercely denied.
"How many people would have crossed if we weren't there today, Frontex? Probably the same. How many would have died? Probably, many more," MSF said on Twitter.
"Where are Frontex boats in a day like this?" it asked. "EU states keep their blind eyes turned".
MSF said in a tweet that one teenager was found dead in a rubber boat whose passengers were rescued by its ship Aquarius. "In 2017, the sea continues to be a graveyard," it said.
In one rescue operation by MOAS, desperate refugees struggled to stay afloat after they slid off their rubber boat off the coast of Libya. Rescuers jumped into the water to help them.