The accident happened when a fire broke out on board a boat packed with an estimated 500 Eritrean and Somali refugees as it neared the end of its journey from the Libyan coast and approached Lampedusa, Italy's southernmost scrap of territory.
The boat's engine stopped working and it began to take on water, prompting some of the passengers to burn a sheet in order to summon help from the island.
But that started a fire on board and terrified migrants rushed to one side of the 65ft-long boat, causing it to capsize about half a nautical mile off the coast.
The Italian coast guard managed to rescue about 155 people but another 220 were still missing.
More than 90 bodies were fished out of the sea, but when divers were sent to inspect the wreck, which sank in about 120ft of water, they saw dozens more bodies trapped in the vessel. Among the victims were at least three children and two pregnant women.
The bodies of the dead were covered in blue plastic sheeting and laid out along the quayside of the island's tiny port, as soldiers wearing protective face masks brought more corpses ashore and emergency officials sobbed with grief.
Angelino Alfano, the deputy prime minister, said Italy urgently needed assistance from Europe in dealing with the exodus of refugees and asylum seekers from Africa and the Middle East.
"This is not an Italian tragedy, this is a European tragedy," he said, speaking in Rome. "Lampedusa has to be considered the frontier of Europe, not the frontier of Italy."
He then flew to Lampedusa and shortly after arriving said: "I saw 93 bodies, a horrific sight that I never thought I would witness. It was a sight that offends the West, that offends the whole of Europe. We cannot remain inactive. We have to get control of this situation."
The tragedy underlined the dangers faced each year by the tens of thousands of desperate migrants and asylum seekers who flee war-torn and poverty-stricken countries in the hope of forging new lives in Europe.
The number of migrants has sharply increased since the Arab Spring of 2011 and the ensuing political chaos in countries like Libya, Tunisia, Egypt and Syria.
Laura Boldrini, who was a spokesman for the United Nations High Commissioner for Refugees before being elected as an MP and the speaker of Italy's lower house of parliament earlier this year, said: "The scale of this tragedy is immense, but the reasons that prompt these people to leave their home countries are the same – war, persecution, violation of their human rights.
"We have seen similar tragedies for years and we've pronounced words of sincere emotion, but without finding any solutions."
In the first six months of this year, nearly 8,000 migrants and asylum-seekers arrived in Italy, while 600 reached neighbouring Malta.
Lampedusa, a speck of land covered in cactus and scrub with a single port and a string of white sand beaches, is where many of the migrants make for because it lies just 80 miles off the coast of Tunisia.
An estimated 13,500 have perished while trying to cross the Mediterranean since 1998, according to Fortress Europe, an internet blog that tracks the deaths.
Europe needed to "step up its efforts to prevent these tragedies and show solidarity both with migrants and with countries that are experiencing increasing migratory flows," said Cecilia Malmstrom, the European Commissioner for home affairs.
"We also need to intensify our efforts to fight criminal networks exploiting human despair so that they cannot continue to put people's lives at risk in small, overcrowded and unseaworthy vessels," she said.
The loss of life was condemned as shameful by the Pope.
"The word that comes to mind is 'shame'," he said. "Let us unite our strengths so that such tragedies never happened again."
On a visit to Lampedusa in July, Francis, whose grandparents emigrated to Argentina from Piedmont in northern Italy before the Second World War, criticised what he called "globalised indifference" to the plight of refugees and asylum seekers.
(Google News: Telegraph)
Photo courtesy Wikipedia.