Washington: A group of Indian workers have launched a hunger strike in front of the White House demanding a US Congressional investigation into their "exploitation" by American companies.

The five workers, who began the "water only" protest at Lafayette Park opposite the US presidential mansion on Wednesday, were among more than 500 Indian welders and pipe fitters who allegedly paid up to $20,000 (Dh73,400) each after being promised green cards and permanent residency in the US.

Seeking "justice from their former employer Signal International and Indian and US recruiters", the workers union claimed the support of the American Federation of Labourers-Congress of Industrial Organisations (AFL-CIO).

"The AFL-CIO and its 10 million members are proud to support the hunger strike by these Signal workers, and their campaign to shed light on the abuses of the ... guest worker programme," said Jon Hiatt, general counsel for the AFL-CIO.