What's more, writes Amnesty International (AI), the global human rights lobby, which brought Ms Zainab's story to light, she is alleged to have confessed to the crime under police interrogation, but "no information is available about any trial that might have taken place".

According to the organisation, while everyone in Saudi Arabia is at risk of human rights violations, foreign nationals are especially vulnerable to abuse. "Some are not paid. Some are beaten. Some are raped," AI says in its report Saudi Arabia: A Secret State of Suffering.

What prevails in Saudi Arabia is a fact of life common in some of its neighbouring countries. In Kuwait, for instance, a Chamber of Commerce official admits that foreign workers are treated "as slaves".

In countries beyond this region, the plight of migrant workers is no better. In Malaysia, for example, where close to 200,000 migrants, largely from Indonesia and the Philippines, work as domestic workers, the press runs stories of migrant workers being tortured by their employers. It is common for these domestic employees to work or be on call from dawn to dusk with little rest in between. And in some households, the workers do not eat at the same time or at the same table as the rest of the household, and when they do, many are likely to get leftovers, say newspaper reports.

According to the International Labour Organization (ILO), there are very few countries where the rights of these workers are respected.

"The exploitation of migrant workers, legal and illegal, is reported everywhere," says Manolo Abella, who heads the department studying labour migrants at the ILO. "They are often victims of unscrupulous recruiters and job agents. Unequal treatment is the rule rather than the exception in most countries, including the most advanced."

Efforts to remedy this situation through a United Nations convention have not been forthcoming, given the few countries that have ratified the International Convention on the Protection of Rights of All Migrant Workers and Their Families.

To date, only nine countries have done so: Bosnia-Herzegovina, Cape Verde, Colombia, Egypt, Morocco, the Philippines, Seychelles, Sri Lanka and Uganda.

Chile and Mexico have only signed the convention.

This convention, which aspires to set far-reaching international standards to protect migrant workers, complements two other ILO conventions dealing with their basic rights.

Article 25 of the convention declares that "migrant workers shall enjoy treatment not less favourable than that which applies to nationals of the state of employment" when it comes to remuneration, conditions of work and terms of employment. This means parity of status between local workers and migrants in overtime, working hours, weekly rest, paid holidays and termination compensation.

The ILO's push for this convention has been bolstered by a new book, Workers without Frontiers: The Impact of Globalisation on International Migration, which highlights the rapid rise in migration patterns around the world.The total number of migrants around the world now surpasses 120 million, up from 75 million in 1965, and continues to grow, affirms the author of the book, Mr Peter Stalker.

In the Persian Gulf, the oil price rise after 1973 triggered an explosion in the demand for labour, he adds. "In Kuwait, in 1996, of a total labour force of 1.1 million, only 176,000 were Kuwaiti citizens."

Likewise, the flow of migrant workers in South Africa "has increased markedly in the post-apartheid era". Mr Stalker estimates the current number of migrants to be anywhere between three to eight million, most of whom come from nearby Mozambique, Zimbabwe and Lesotho.

In Latin America, there have been flows to Argentina, Brazil and Mexico. "An estimated 200,000 undocumented migrants from Bolivia, Paraguay and Peru live and work in Argentina."

Among the industrialised countries, Mr Stalker has identified Germany as having served as "a magnet" for foreign workers following the collapse of communism. In the years 1988-1994, net immigration into both parts of Germany totalled four million, two million of them ethnic Germans from the former Soviet Union.

A study done by the ILO reveals that a significant number of migrant workers in the world are women. In Asia, for instance, the majority of them come from Indonesia, the Philippines and Sri Lanka, and they are often employed as domestic servants.

In Europe, on the other hand, the women are employed as nurses, retail workers and waitresses. Nevertheless, hardly any of them enjoy the rights the ILO is trying to secure. "In some regions of the world, calls for their rights have not been heeded at all and the institutions to protect migrant workers do not exist," laments Abella.

Such a scenario has prompted labour rights activists and women's groups to step in and fill the void. In Sri Lanka, for example, a coalition of NGOs and activists have created the Action Network for Migrant Workers (ANMW).

This network, according to its founders, seeks to inform Sri Lanka's migrant workers in the Middle East about their rights, provide counselling, and offer legal aid. Activists feel that "active intervention" is necessary all over the world.

As one government official, who supports the ANMW puts it: "The distinction between slavery and employment in this instance remains rather thin."Inter Press Service