Updated 9.30 pm with migrant rescue details
Pictures shot by a Maltese photographer show the drama as 134 sub-Saharan migrants were rescued off the Libyan coast.
The pictures shot by Reuters and former Times of Malta photographer Darrin Zammit Lupi show the migrants trying to stay afloat after falling off their rubber dinghy during a rescue operation by the Malta-based NGO Migrant Offshore Aid Station (MOAS) ship.
One picture shows a migrant trying to reach out to help a man submerged underwater as he holds his hand out, amid a sea of lifejackets.
The rescue was carried out in international waters some 15 nautical miles off the coast of Zawiya in Libya.
When contacted, Mr Zammit Lupi said it was thanks to the quick reactions and professionalism of the MOAS rescuers that there were no victims.
"Two migrants had gone completely under, but the rescue swimmer managed to get to them before they drowned."
More than 2,000 rescued in one day
It was a dramatic day for marine rescuers, with more than 2,000 migrants trying to reach Europe plucked from the Mediterranean in a series of dramatic rescue missions.
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 migrants on 16 rubber dinghies and three small wooden boats.
The medical charity Medecins Sans Frontieres (MSF) said in a tweet that one teenager was found dead in a rubber boat whose passengers were rescued by its ship Aquarius.
"The sea continues to be a graveyard," MSF said in a Tweet.
The coast guard spokesman confirmed that one person had died but gave no details.
MSF said two of their ships, Aquarius and Prudence, had rescued about 1,000 people in nine boats.
Those rescued by the MOAS and MSF ships were transferred to Italian coast guard ships, which had rescued other migrants, to be taken to Italian ports.
According to the International Organisation for Migration, nearly 32,000 migrants have arrived in Europe by sea so far this year. More than 650 have died or are missing.