Migrants From Myanmar, Shunned by Malaysia, Are Spotted Adrift in Andaman Sea

(CNN)A top Malaysian official says the surge of migrants from Myanmar and Bangladesh seeking asylum in his country and neighboring Indonesia in recent days is unwelcome -- and his government will turn back any illegal arrivals.

"We cannot welcome them here," Malaysian Deputy Home Minister Wan Junaidi Jaafar told CNN by phone.

"If we continue to welcome them, then hundreds of thousands will come from Myanmar and Bangladesh."

The comments come as humanitarian groups issue urgent warnings about the fates of estimated thousands of desperate migrants stranded aboard rickety traffickers' ships in the busy Strait of Malacca and nearby waters, looking for a safe harbor to take them in.

Jeff Labovitz, spokesman for the International Organization Migration in Bangkok, told CNN Thursday that Thai authorities were dealing with one such vessel with 350 passengers on board -- including "many women and children" -- after it had been abandoned by the trafficker operating the vessel.

"We don't know if they're going to let it disembark," he said.

He said those on board had earlier been given food and water by Malaysian authorities, before being turned around.

Crisis spreads

The humanitarian crisis engulfing Myanmar's Rohingya -- a persecuted Muslim minority who are effectively stateless in majority-Buddhist Myanmar -- has begun impacting other southeast Asian countries as desperate migrants arrive in their waters and on their shores, seeking asylum.

More than 1600 migrants -- both Rohingya and economic migrants from Bangladesh -- have landed in Malaysia and Indonesia since Sunday, officials say, after Thai officials began cracking down on human trafficking camps operating in the country's south near the Malaysian border, disrupting established people smuggling networks.

The crackdown came following the discovery of dozens of bodies in trafficking camps in the jungle.

With the Thai pipeline for illegal migrants closed, overcrowded traffickers' boats have begun offloading their human cargo on the shores of Malaysia and Indonesia -- Muslim-majority countries that have shown sympathy for the Rohingya in the past.

Alternatively, crews have simply abandoned them to drift.

Rights groups have called on governments in the region to carry out urgent search and rescue operations to avoid a catastrophe for thousands stranded at sea.

"It's harrowing to think that hundreds of people are right now drifting in a boat perilously close to dying, without food or water, and without even knowing where they are," said Kate Schuetze, Asia Pacific researcher for rights group Amnesty International.

'Send them back'

But despite the calls to rescue the imperiled migrants, officials from Malaysia and Indonesia have said they have instead refueled and restocked migrant vessels and sent them on their way.

"If the boat is still good and can sail back, we give them food, and drink and fuel and send them back," the Malaysian minister said.

He denied reports that Malaysian authorities had "pushed back" a boat with more than 500 migrants off the coast of northern Penang Wednesday after providing them with fuel and supplies -- but said that doing so would be consistent with government policy, provided the vessel was seaworthy.