People smugglers are "trading in misery" by charging hundreds of pounds to take desperate refugees on dangerous boat journeys but letting young children go for free, a charity worker said.

Three-year-old Aylan Kurdi, his older brother Galip, 5, and their mother Rehan all drowned just minutes after attempting to cross from Bodrum in Tukey to the Greek island of Kos on Wednesday.

Aylan's aunt has spoken of her distress after telling how she sent the family five thousand dollars to help may smugglers for their trip.

"I blame myself because my brother does not have money," said Tima Kurdi.

Chris Tidey, who works with Unicef, said young children are especially vulnerable.

He told the Sunday Mirror: "We've spoken to people who have paid up to 1,200 euro  and their infants got in the dinghy for free.

"Their older kids were 10 so they were charged 600 euro - half price.

"It's trading in misery. All the children, especially those unaccompanied or separated from their families, are -particularly vulnerable."

He added that many refugees he had spoken to told him they were advised to "cut the boat and start yelling for help" if they got into difficulties in the water.

The International Organisation for Migration said at least 364,000 people have crossed the Mediterranean to Europe this year, of which more than 2,800 are thought to have died.