Thousands of people are stranded at sea as Malaysia turned away a boat crammed with more than 500 migrants.
Indonesia and Thailand also appeared unwilling to provide refuge to men, women and children, despite appeals by the UN High Commission for Refugees, international aid agencies and rights activists, who warned lives were at risk.
Immigrants from Myanmar and Bangladesh arrive at the Langkawi police station's multi purpose hall in Langkawi, Malaysia
Fearing arrests, captains tied to trafficking networks have in recent days abandoned ships in the busy Malacca Strait and surrounding waters, leaving behind their human cargo, in many cases with little food or water, according to survivors.
Around 1,600 have been rescued, but an estimated 6,000 remain stranded at sea.
Malaysian deputy home minister Wan Junaidi said those on board the boat, Rohingya Muslims and Bangladeshis, were given provisions and then sent on their way.
"What do you expect us to do?" he said.
"We have been very nice to the people who broke into our border.
"We have treated them humanely but they cannot be flooding our shores like this.
"We have to send the right message that they are not welcome here," he said.
The boat was found yesterday off the cost of northern Penang state three days after more than a thousand refugees landed on nearby Langkawi island.
South-east Asia, which for years tried to quietly ignore the plight of Burma's 1.3 million Rohingya, now finds itself caught in a spiralling humanitarian crisis that in many ways it helped create.
In the last three years, more than 120,000 members of the Muslim minority have boarded ships to flee to other countries, according to the UN refugee agency.
But no governments in the region appear willing to take them in, fearing that accepting a few would result in an unstoppable flow of poor, uneducated migrants.
At the same time, they have for years bowed to the wishes of Burma at regional conferences, avoiding all discussions of state-sponsored discrimination against the Rohingya.
Denied citizenship by national law, members of the Rohingya minority are effectively stateless. They have limited access to education or adequate health care and cannot move around freely.
They have been attacked by the military and chased from their homes and land by extremist Buddhist mobs.
With the crisis now reaching a crescendo, Thailand said it would hold an emergency meeting later this month in Bangkok to discuss the exodus and "root causes".
Representatives from 15 countries, including the US and Australia, are expected to attend.
Thailand reiterated this week that its policy is to "help on" boat people, giving those who end up in their waters food, water and other provisions, and then sending them on their way.
Indonesia, which did take 600 Rohingya and Bangaleshis on Sunday, later turned away a boat.
But a foreign ministry spokesman denied it had a "push back" policy, saying the Malaysian-bound vessel strayed into its waters by accident.
"This is a grave humanitarian crisis demanding an immediate response," said Matthew Smith, executive director of human rights group Fortify Rights.
"Lives are on the line. Regional governments should act decisively to rescue and protect asylum seekers and trafficking survivors, not drive them back out to sea."
Increasingly over the years, Rohingya boarding boats in the Bay of Bengal have been joined by people from neighbouring Bangladeshi, most of them seeking an escape from poverty.
For those fleeing, the first stop until recently was Thailand, where migrants were held in jungle camps until their families could raise hefty ransoms so they could continue onward.
Recent security crackdowns forced the smugglers to change tactics, instead holding people on large ships parked offshore.
Initially they were shuttled to shore in groups on smaller boats after their "ransoms" were paid.
But as agents and brokers on land got alarmed by arrests - not just of traffickers but also police and politicians - they went into hiding.
That created a bottleneck, with migrants stuck on boats for weeks.
Malaysia, which is not a signatory of international conventions on refugees, is host to more than 150,000 refugees and asylum seekers, the majority from Burma.
More than 45,000 of them are Rohingyas, according to the UN refugee agency.