Reports and warnings came in from as far apart as Britain, Sweden, Sri Lanka, Thailand and Hong Kong of criminals taking advantage of the chaos to rape survivors in Sri Lanka or plunder the homes of European tourists reported missing.

In stark contrast to a worldwide outpouring of humanitarian aid in response to the December 26 tsunami, whose death toll stood at nearly 146,000 people by Tuesday, a women's group in Sri Lanka said rapists were preying on homeless survivors.

"We have received reports of incidents of rape, gang rape, molestation and physical abuse of women and girls in the course of unsupervised rescue operations and while resident in temporary shelters," the Women and Media Collective group said.

The group urged the authorities to urgently beef up security at refuge centres and establish a means for victims to press charges against their assailants.

Most of those in the refugee centres are women and children, while male survivors are largely attempting to pick through the rubble of their shattered homes and businesses.

The group said that while it had no firm data on attacks, the mobility of women "continues to be restricted due to fear of sexual violence".

Meanwhile the United Nations Children's Fund (UNICEF) said yesterday that human traffickers are preying on children made homeless or orphaned by the tsunami disaster in the devastated Indonesian province of Aceh.

UNICEF's spokesman for Indonesia, John Budd, told AFP there had been one confirmed case of a child being smuggled out of Aceh to the nearby North Sumatran capital of Medan for trafficking purposes.

And he said UNICEF's Malaysian office had received an SMS on Tuesday advertising 300 orphans from Aceh aged between three and 10 who could be bought.

"It's chilling," Budd said. "What this indicates is that they have got children or they have a network where they can identify a child and take them."

The Indonesian government has also moved to head off the trafficking of children from Aceh by placing a ban on any child under the age of 16 leaving Aceh without their parents.

"The aim of the travel ban is to ensure there is no adoption and to prevent any sale and trafficking of children from Aceh," Social Affairs Ministry spokesman Heri Krisitanto told AFP.

A ban on any adoptions in Aceh has also been imposed for the same reason, he said.

National police detective chief Commissioner General Suyitno Landung also said Tuesday that the issue was of deep concern and authorities were trying to register all homeless or orphaned children so they could be tracked.

"We have deployed officers to relief centres to collect data on the children," detikom on-line news service quoted Landung as saying.

The government has estimated that 35,000 children have been made homeless, orphaned or separated from their parents in Aceh, which remains in chaos more than a week after the tsunamis destroyed much of the province's west coast.

Budd said there had been many reports of child trafficking in Aceh over the past few days that UNICEF, local non-government organisations and the Indonesian government had been trying to confirm.

But he said UNICEF was "adamant" that at least one child had been stolen and taken to Medan, saying the report came from a very reliable local non-government organisation.

He also said that Medan was a well-known centre for the trade in children.

"There are ruthless criminal gangs based out of Medan who have been involved in this for a very long time," he said.

Authorities have in the past arrested people on child trafficking charges in Medan, where the rings are well known for selling babies for adoption to people in Malaysia and Singapore.

Budd also said that UNICEF had received reports from local non-government organisations that "hundreds" of children from Aceh had been taken to Jakarta since the disaster happened.

"We don't know if they have been brought to Jakarta for their own protection or whether it is something more sinister," he said.

"Everybody is deeply worried about this."

The Jakarta Post daily also quoted on Tuesday a Medan-based non-government organisation as saying that 20 children had been smuggled out of Aceh to Bandung on neighbouring Java island, as well as Malaysia.

Aceh Sepakat Foundation spokesman Masriza said a trafficking gang posing as a charitable foundation was responsible.

"Usually, the targets are babies and children under 15," the Jakarta Post quoted him as saying.

Save the Children also warned that youngsters orphaned by the tsunami were vulnerable to sexual exploitation. "The experience of earlier catastrophes is that children are especially exposed," said its Swedish chief, Charlotte Petri Gornitzka.

In Thailand thieves disguised as police and rescue workers have looted luggage and hotel safes around Khao Lak beach, where the tsunami killed up to 3,000 people.

Sweden sent seven police officers there on Monday to investigate the reported kidnap of a Swedish boy of 12 whose parents were carried off by the wave. (Reuters, AFP)