The footage shows dozens of people clinging to a rubber dinghy as they struggle to stay afloat.

After a group of migrants’ overcrowded vessel sank off the coast of Libya on Saturday — an episode in which at least 64 of them drowned in the Mediterranean Sea — the rescue operation was recorded by a member of the Italian Coast Guard as the first responders scrambled to save lives.

The group in the dinghy, which migration officials said was aided by smugglers and bound for Italy, became the latest casualties in a continuing crisis. More than 3,000 refugees and migrants died in the Mediterranean last year while trying to make their way to Europe.

The deaths on Saturday focused attention on the dangerous central Mediterranean crossing between Libya and Italy, where most of those deaths took place, and prompted calls from the United Nations migration agency for a comprehensive policy to address the humanitarian crisis.