Tortured, sold as a slave three times and haunted with guilt after watching his cousin drown, Bangladeshi teenager Khaled Hossain fears he will never recover from the trauma of his failed attempt to reach Europe.

Even as hundreds of thousands surge into Bangladesh fleeing violence in Myanmar hoping for a better life, there is an exodus of those who feel the country is at breaking point and salvation lies elsewhere.

Experts warn the Rohingya refugee crisis and the strain on resources will push more disaffected Bangladeshis to attempt risky journeys in a bid to make their fortunes elsewhere.

Like Hossain, tens of thousands are travelling from the South Asian nation to Libya to make the perilous boat trip to Italy.

I was excited that within hours we would be in Italy. All my family's financial troubles will be over. I thought I could now prove myself worthy to my paralysed father," the 18-year-old told AFP.

Instead many are sold as slaves before they even reach port, and those that do secure a boat -- like Hossain's young cousin -- may not survive the journey.

"I am consumed by guilt," said Hossain, who has returned, broken, to Bangladesh. 

"I will have to live with his death for the rest of my life," he added.

- Crushed to death -

More than 100 people were squeezed into the tiny boat he and his cousin Farid took from Libya to Italy, many were Africans, but there were dozens from Hossain's hometown of Beanibazar as well as elsewhere across the country. 

Three hours after the 30-foot (10-metre) plastic vessel had set off from Libya, it broke down and started to sink.

There was "panic", Hossain recounted. One Bangladeshi youth was crushed to death in the rush and other passengers jumped into the sea, never to be seen again.

Several emptied cans of petrol on the boat floor so they could use the containers to float in the water.

"Our feet burned when they dipped in the petrol," he explained, adding that Farid jumped into the sea to escape the burning. 

The teenager saw a ship on the horizon and attempted to swim for help, but did not survive.

"I saw his lifeless body floating," Hossain recalled. 

More than 2,700 people have died attempting to cross the Mediterranean so far this year, according to the UN, with Bangladeshis top of the list of people rescued.

Hossain was plucked from the sea by a Libyan gang and spent three months in the war-torn nation working as a slave on construction sites.

He says he was sold at least three times. His father, severely debilitated after a stroke, paid $12,000 in total to secure his release.

Hossain recalled: "We were tortured. Many were raped and sodomised at gunpoint."

- 'Deaths don't matter' -

Bangladesh's population has soared in recent years and despite reasonable growth over the past decade, opportunities for work are limited. 

The number of Bangladeshis on the Libya-to-Italy route has risen from a few dozen in 2014 to about 11,000 from June 2016 to March this year, according to official figures, though some estimates put the figure as high as 30,000. 

In Beanibazar alone, an estimated 1,000 young men have made the $10,000 journey in the past year, council chairman Ataur Rahman Khan told AFP.

"Young men are desperate to go to Italy via Libya. Fathers are borrowing money and mothers are selling heirlooms to pay the traffickers," Khan said.

The situation may worsen as the arrival of more than half a million Rohingya refugees who have fled an army crackdown in Myanmar's troubled Rakhine state since puts an immense strain on Bangladesh's resources. 

Authorities have allocated a huge swathe of land in the country's southeast in an effort to confine some 800,000 Rohingya into a settlement set to be the world's largest refugee camp.

Migration expert Jalal Uddin Sikder told AFP that if authorities "failed to find a solution" to the refugee crisis, then the situation would "fuel" the exodus out if Bangladesh.

Sikder added traffickers use rare success stories of migrants who have reached Europe to lure tens of thousands of others to follow suit.

He explained: "They sell stories of success to jobless youths, causing enormous peer pressure in families. One or two deaths at sea or reports of kidnappings just don't matter anymore."