0655 GMT November 13, 2019
Along with accusations of corruption during its World Cup bid, Qatar has long been under fire from rights groups for labor abuses. Last week, world soccer body FIFA urged Qatar to hasten improvements for builders on World Cup sites and said it would monitor conditions, Reuters reported.
Qatar, an energy exporter which has the highest income per capita in the world, is also under pressure from the United Nations to address workers' rights before World Cup construction peaks in 2017.
Laborer Jaleshwar Prasad, 48, fell unconscious on Wednesday while performing steel work at Al Bayt stadium in Al-Khor, 50km (31 miles) north of Doha, a witness told Reuters.
Organizers said the death was not caused by working conditions.
"Al-Khor Hospital reported the cause of death as cardiac arrest," the Qatar's Supreme Committee for Delivery and Legacy of the 2022 World Cup said in a statement.
"The family of Mr. Prasad was informed of the tragedy immediately. A full investigation is underway."
Qatar's efforts to become the competition's first Arab host have been dampened by accusations including that workers were forced to live in squalor and to work without proper access to water and shelter in the blazing sun.
About 5,100 construction workers from Nepal, India and Bangladesh are building stadiums in the country.
Unions and labor protests are banned and authorities penalize dissent with jail terms or immediate deportation.
Prasad is the third Indian employed on a World Cup site to die of a heart attack in the last six months, according to a February report by the Supreme Committee.
Qatar's Supreme Committee says there have been no work-related fatalities on World Cup sites, but law firm DLA Piper, in a review for the government in 2013, found evidence of dozens of work-related deaths among migrant laborers from South Asia.
Qatar's government has also denied claims there are higher instances of heart attacks among construction workers and does not publish independently-verified statistics on worker-related injuries and fatalities.