After two hours locked below deck on an Italy-bound smuggling boat, the two teenagers from Bangladesh asked to go up top to relieve themselves. The decision probably saved their lives.
The boys, Nasir and Riajul, both 17, were among 28 survivors from a smuggling vessel that sank in the Mediterranean Sea late Saturday after sailing from Libya. Lost were more than 700 people, mostly sub-Saharan Africans, but also some Asians.
"They let us go up, and we never went back down to the lower deck, where you couldn't breathe and where people were sitting on top of each other," said Nasir, who is from Kuliarchar.
The incident appears to have been the deadliest such shipwreck to date, authorities say. The disaster has prompted European leaders to review search-and-rescue efforts and consider a new policy in the Mediterranean.
On Tuesday, the boys provided some of the first survivor accounts of the disaster.
The boat carrying the pair and hundreds of others tipped over just as a merchant ship was about to rescue the migrants, the two said.
"We were really happy to see the ship," recalled Riajul, who, along with Nasir, spoke Tuesday at a reception center for migrants outside this Sicilian port city.
However, he said, the two vessels — the container ship and the smuggling craft, a converted fishing boat — collided amid the tumult.
Those who were locked below deck had no chance.
Both boys were picked up after slipping into the water, where they floated for half an hour. Unlike many others on board, they knew how to swim.
"We could swim, and saw bodies floating in the darkness," said Nasir. Someone helped him stay afloat in the darkness.
Riajul, who is from Dhaka, said, "We heard people screaming 'Oh! Oh! Help us!'"
Two teenagers from Somalia also survived.
One of the Somalis, a 16-year-old, told officials with the charity Save the Children that he had crossed the Sahara desert from Sudan to reach Ajdabiya in Libya, where he was jailed for nine months until his family sent money to his jailers to free him.
Some estimates put the number who died in the latest incident at more than 800. Many of those who perished were trapped in a lower deck and had no chance of escaping, authorities said.
The staggering weekend death toll is the highest reported to date in a single incident and has prompted calls for a new migrant strategy from European leaders. Many expect officials to institute a stepped-up search-and-rescue effort as the spring and summer bring a new wave of refugees.
The International Organization for Migration issued a statement saying that last year's estimated death total — 3,279 migrants — could be surpassed this year in a matter of weeks. At this time last year, the group noted, only 56 deaths of migrants in the Mediterranean had been reported; the bulk of the fatalities came later in the year.
This year's toll already stands at an estimated 1,727, the organization said.
Save the Children warned that if the rate of drownings in the Mediterranean continued, 2,500 children would lose their lives this year.
Few migrant boats leaving Libya make it to the Italian coast, officials and monitors say. Instead, the aim of many migrants is to be rescued at sea and taken to Italy, the first entry point to Europe and a new life. In light of that, smugglers are probably inclined to make only a minimum investment in making their craft seaworthy, experts note, because the boats are making a one-way trip.
The smuggling business is extremely profitable, with thousands of potential clients waiting in staging areas in Libya and elsewhere to be taken to Europe, authorities say.
Migrant smugglers have thrived in Libya since the 2011 overthrow of Moammar Kadafi, whose government had vigorously worked with Italian authorities to reduce the flow. An aerial bombing campaign by U.S. and European warplanes in 2011 helped opposition forces seize power. Libya has since experienced political turmoil and the rise of Islamist militias.
Late Monday, Italian authorities said they had arrested two people from the smuggling ship in the latest disaster. The two suspects, a Tunisian described as the captain and a Syrian said to have been a crew member, were among the 28 known survivors brought to Italy. Only 24 bodies have been found, authorities said.
The two are being held in Sicily on charges including multiple counts of murder and people smuggling, authorities said.
New accounts have been emerging about the doomed craft and the frantic rescue effort, which unfolded late Saturday and early Sunday.
The survivors plucked from the sea "didn't understand if they were dead or alive," Gianluigi Bove, the captain of an Italian coast guard ship involved in the rescue, told Italy's La Repubblica newspaper. His ship had retrieved the bodies of some of the dead, along with the survivors.
"They didn't understand if they had survived or were like those corpses laid out in front of them," the captain said.
Even as the tragedy drew international attention, the steady flow of rickety boats bound for Europe continued.
On Monday, the Italian coast guard picked up 638 migrants from six inflatable dinghies in the Mediterranean, authorities said. On Tuesday, 446 migrants were taken off a boat 80 nautical miles southeast of the Italian region of Calabria as the craft took on water.
Kington is a special correspondent.